What is $int sqrtcos(2Q) / sin(Q) ,mathrmdQ$? [closed]

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What is
$$
int fracsqrtcos(2Q)sin(Q) ,mathrmdQ?
$$




I have tried all the method which is possible but could not able to find the solution. Can anyone please tell me the solution of this problem.







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closed as off-topic by Adrian Keister, Theoretical Economist, Leucippus, Jendrik Stelzner, user91500 Aug 28 at 9:12


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – Adrian Keister, Theoretical Economist, Leucippus, Jendrik Stelzner, user91500
If this question can be reworded to fit the rules in the help center, please edit the question.








  • 4




    Is this what you meant: $$int fracsqrtcos 2qsin q , mathrmdq$$
    – Tolaso
    Aug 27 at 12:30







  • 1




    Welcome to MSE. It will be more likely that you will get an answer if you show us that you made an effort. This should be added to the question rather than in the comments.
    – José Carlos Santos
    Aug 27 at 12:31






  • 1




    Wolfram Alpha looks rather unpleasant
    – gt6989b
    Aug 27 at 12:36











  • Tip: expand the double-angle cosine using the double angle formula.
    – FGSUZ
    Aug 27 at 13:05










  • I done that still can't solve
    – Rajesh Gupta
    Aug 27 at 13:09














up vote
1
down vote

favorite
1













What is
$$
int fracsqrtcos(2Q)sin(Q) ,mathrmdQ?
$$




I have tried all the method which is possible but could not able to find the solution. Can anyone please tell me the solution of this problem.







share|cite|improve this question














closed as off-topic by Adrian Keister, Theoretical Economist, Leucippus, Jendrik Stelzner, user91500 Aug 28 at 9:12


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – Adrian Keister, Theoretical Economist, Leucippus, Jendrik Stelzner, user91500
If this question can be reworded to fit the rules in the help center, please edit the question.








  • 4




    Is this what you meant: $$int fracsqrtcos 2qsin q , mathrmdq$$
    – Tolaso
    Aug 27 at 12:30







  • 1




    Welcome to MSE. It will be more likely that you will get an answer if you show us that you made an effort. This should be added to the question rather than in the comments.
    – José Carlos Santos
    Aug 27 at 12:31






  • 1




    Wolfram Alpha looks rather unpleasant
    – gt6989b
    Aug 27 at 12:36











  • Tip: expand the double-angle cosine using the double angle formula.
    – FGSUZ
    Aug 27 at 13:05










  • I done that still can't solve
    – Rajesh Gupta
    Aug 27 at 13:09












up vote
1
down vote

favorite
1









up vote
1
down vote

favorite
1






1






What is
$$
int fracsqrtcos(2Q)sin(Q) ,mathrmdQ?
$$




I have tried all the method which is possible but could not able to find the solution. Can anyone please tell me the solution of this problem.







share|cite|improve this question















What is
$$
int fracsqrtcos(2Q)sin(Q) ,mathrmdQ?
$$




I have tried all the method which is possible but could not able to find the solution. Can anyone please tell me the solution of this problem.









share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Aug 27 at 13:36









Jendrik Stelzner

7,63121037




7,63121037










asked Aug 27 at 12:29









Rajesh Gupta

92




92




closed as off-topic by Adrian Keister, Theoretical Economist, Leucippus, Jendrik Stelzner, user91500 Aug 28 at 9:12


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – Adrian Keister, Theoretical Economist, Leucippus, Jendrik Stelzner, user91500
If this question can be reworded to fit the rules in the help center, please edit the question.




closed as off-topic by Adrian Keister, Theoretical Economist, Leucippus, Jendrik Stelzner, user91500 Aug 28 at 9:12


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – Adrian Keister, Theoretical Economist, Leucippus, Jendrik Stelzner, user91500
If this question can be reworded to fit the rules in the help center, please edit the question.







  • 4




    Is this what you meant: $$int fracsqrtcos 2qsin q , mathrmdq$$
    – Tolaso
    Aug 27 at 12:30







  • 1




    Welcome to MSE. It will be more likely that you will get an answer if you show us that you made an effort. This should be added to the question rather than in the comments.
    – José Carlos Santos
    Aug 27 at 12:31






  • 1




    Wolfram Alpha looks rather unpleasant
    – gt6989b
    Aug 27 at 12:36











  • Tip: expand the double-angle cosine using the double angle formula.
    – FGSUZ
    Aug 27 at 13:05










  • I done that still can't solve
    – Rajesh Gupta
    Aug 27 at 13:09












  • 4




    Is this what you meant: $$int fracsqrtcos 2qsin q , mathrmdq$$
    – Tolaso
    Aug 27 at 12:30







  • 1




    Welcome to MSE. It will be more likely that you will get an answer if you show us that you made an effort. This should be added to the question rather than in the comments.
    – José Carlos Santos
    Aug 27 at 12:31






  • 1




    Wolfram Alpha looks rather unpleasant
    – gt6989b
    Aug 27 at 12:36











  • Tip: expand the double-angle cosine using the double angle formula.
    – FGSUZ
    Aug 27 at 13:05










  • I done that still can't solve
    – Rajesh Gupta
    Aug 27 at 13:09







4




4




Is this what you meant: $$int fracsqrtcos 2qsin q , mathrmdq$$
– Tolaso
Aug 27 at 12:30





Is this what you meant: $$int fracsqrtcos 2qsin q , mathrmdq$$
– Tolaso
Aug 27 at 12:30





1




1




Welcome to MSE. It will be more likely that you will get an answer if you show us that you made an effort. This should be added to the question rather than in the comments.
– José Carlos Santos
Aug 27 at 12:31




Welcome to MSE. It will be more likely that you will get an answer if you show us that you made an effort. This should be added to the question rather than in the comments.
– José Carlos Santos
Aug 27 at 12:31




1




1




Wolfram Alpha looks rather unpleasant
– gt6989b
Aug 27 at 12:36





Wolfram Alpha looks rather unpleasant
– gt6989b
Aug 27 at 12:36













Tip: expand the double-angle cosine using the double angle formula.
– FGSUZ
Aug 27 at 13:05




Tip: expand the double-angle cosine using the double angle formula.
– FGSUZ
Aug 27 at 13:05












I done that still can't solve
– Rajesh Gupta
Aug 27 at 13:09




I done that still can't solve
– Rajesh Gupta
Aug 27 at 13:09










1 Answer
1






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1
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First notice that
beginequation
cosleft(2xright)=cos^2left(xright)-sin^2left(xright)
endequation
and
beginequation
sinleft(xright)=dfractanleft(xright)secleft(xright)
endequation
so
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleint
sec^2(x) cdotdfracsqrt1-tan^2left(xright)tanleft(xright)left(tan^2left(xright)+1right),mathrmdx
endequation
Change of variable as
beginequation
u = tan (x)
endequation
we get
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleintdfracsqrt1-u^2uleft(u^2+1right),mathrmdu
endequation
Another change of variable as
beginequation
v = sqrt1 - u^2
endequation
gives us
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=-displaystyleintdfracv^2left(v^2-2right)left(v^2-1right),mathrmdv
endequation
Now let's factor the denominator as
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleintdfracv^2left(v-1right)left(v+1right)left(v^2-2right),mathrmdv
endequation
Then perform partial fraction decomposition
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleintleft(dfrac2v^2-2+dfrac12left(v+1right)-dfrac12left(v-1right)right)mathrmdv
=
2A + frac12B - frac12 C
endequation
Let's do $A$,
beginequation
A = displaystyleintdfrac1v^2-2,mathrmdv
=
=displaystyleintdfrac1left(v-sqrt2right)left(v+sqrt2right),mathrmdv
=displaystyleintleft(dfrac12^frac32left(v-sqrt2right)-dfrac12^frac32left(v+sqrt2right)right)mathrmdv
endequation
which s
beginequation
A
=
=dfraclnleft(v-sqrt2right)2^frac32-dfraclnleft(v+sqrt2right)2^frac32
endequation
Now, similarly
beginequation
B =lnleft(v+1right)
endequation
and
beginequation
C =lnleft(v-1right)
endequation
Plugging all $A,B,C$ back we get
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=-dfraclnleft(v+sqrt2right)sqrt2+dfraclnleft(v-sqrt2right)sqrt2+dfraclnleft(v+1right)2-dfraclnleft(v-1right)2
endequation
Undoing the change of variable $v = sqrt1 - u^2$, we get
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx=dfraclnleft(sqrt1-u^2+sqrt2right)sqrt2-dfraclnleft(sqrt1-u^2-sqrt2right)sqrt2-dfraclnleft(sqrt1-u^2+1right)2+dfraclnleft(sqrt1-u^2-1right)2
endequation
Undoing the other change of variable $u = tan (x)$, we get
beginequation
dfraclnleft(sqrt1-tan^2left(xright)+sqrt2right)sqrt2-dfraclnleft(sqrt1-tan^2left(xright)-sqrt2right)sqrt2-dfraclnleft(sqrt1-tan^2left(xright)+1right)2+dfraclnleft(sqrt1-tan^2left(xright)-1right)2
endequation
Now, depending where you're integrating, you've got to have absolute values in the arguments of the logarithms.






share|cite|improve this answer






















  • what is the mistake @RajeshGupta?
    – Ahmad Bazzi
    Aug 27 at 15:51

















1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes








up vote
1
down vote













First notice that
beginequation
cosleft(2xright)=cos^2left(xright)-sin^2left(xright)
endequation
and
beginequation
sinleft(xright)=dfractanleft(xright)secleft(xright)
endequation
so
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleint
sec^2(x) cdotdfracsqrt1-tan^2left(xright)tanleft(xright)left(tan^2left(xright)+1right),mathrmdx
endequation
Change of variable as
beginequation
u = tan (x)
endequation
we get
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleintdfracsqrt1-u^2uleft(u^2+1right),mathrmdu
endequation
Another change of variable as
beginequation
v = sqrt1 - u^2
endequation
gives us
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=-displaystyleintdfracv^2left(v^2-2right)left(v^2-1right),mathrmdv
endequation
Now let's factor the denominator as
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleintdfracv^2left(v-1right)left(v+1right)left(v^2-2right),mathrmdv
endequation
Then perform partial fraction decomposition
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleintleft(dfrac2v^2-2+dfrac12left(v+1right)-dfrac12left(v-1right)right)mathrmdv
=
2A + frac12B - frac12 C
endequation
Let's do $A$,
beginequation
A = displaystyleintdfrac1v^2-2,mathrmdv
=
=displaystyleintdfrac1left(v-sqrt2right)left(v+sqrt2right),mathrmdv
=displaystyleintleft(dfrac12^frac32left(v-sqrt2right)-dfrac12^frac32left(v+sqrt2right)right)mathrmdv
endequation
which s
beginequation
A
=
=dfraclnleft(v-sqrt2right)2^frac32-dfraclnleft(v+sqrt2right)2^frac32
endequation
Now, similarly
beginequation
B =lnleft(v+1right)
endequation
and
beginequation
C =lnleft(v-1right)
endequation
Plugging all $A,B,C$ back we get
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=-dfraclnleft(v+sqrt2right)sqrt2+dfraclnleft(v-sqrt2right)sqrt2+dfraclnleft(v+1right)2-dfraclnleft(v-1right)2
endequation
Undoing the change of variable $v = sqrt1 - u^2$, we get
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx=dfraclnleft(sqrt1-u^2+sqrt2right)sqrt2-dfraclnleft(sqrt1-u^2-sqrt2right)sqrt2-dfraclnleft(sqrt1-u^2+1right)2+dfraclnleft(sqrt1-u^2-1right)2
endequation
Undoing the other change of variable $u = tan (x)$, we get
beginequation
dfraclnleft(sqrt1-tan^2left(xright)+sqrt2right)sqrt2-dfraclnleft(sqrt1-tan^2left(xright)-sqrt2right)sqrt2-dfraclnleft(sqrt1-tan^2left(xright)+1right)2+dfraclnleft(sqrt1-tan^2left(xright)-1right)2
endequation
Now, depending where you're integrating, you've got to have absolute values in the arguments of the logarithms.






share|cite|improve this answer






















  • what is the mistake @RajeshGupta?
    – Ahmad Bazzi
    Aug 27 at 15:51














up vote
1
down vote













First notice that
beginequation
cosleft(2xright)=cos^2left(xright)-sin^2left(xright)
endequation
and
beginequation
sinleft(xright)=dfractanleft(xright)secleft(xright)
endequation
so
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleint
sec^2(x) cdotdfracsqrt1-tan^2left(xright)tanleft(xright)left(tan^2left(xright)+1right),mathrmdx
endequation
Change of variable as
beginequation
u = tan (x)
endequation
we get
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleintdfracsqrt1-u^2uleft(u^2+1right),mathrmdu
endequation
Another change of variable as
beginequation
v = sqrt1 - u^2
endequation
gives us
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=-displaystyleintdfracv^2left(v^2-2right)left(v^2-1right),mathrmdv
endequation
Now let's factor the denominator as
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleintdfracv^2left(v-1right)left(v+1right)left(v^2-2right),mathrmdv
endequation
Then perform partial fraction decomposition
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleintleft(dfrac2v^2-2+dfrac12left(v+1right)-dfrac12left(v-1right)right)mathrmdv
=
2A + frac12B - frac12 C
endequation
Let's do $A$,
beginequation
A = displaystyleintdfrac1v^2-2,mathrmdv
=
=displaystyleintdfrac1left(v-sqrt2right)left(v+sqrt2right),mathrmdv
=displaystyleintleft(dfrac12^frac32left(v-sqrt2right)-dfrac12^frac32left(v+sqrt2right)right)mathrmdv
endequation
which s
beginequation
A
=
=dfraclnleft(v-sqrt2right)2^frac32-dfraclnleft(v+sqrt2right)2^frac32
endequation
Now, similarly
beginequation
B =lnleft(v+1right)
endequation
and
beginequation
C =lnleft(v-1right)
endequation
Plugging all $A,B,C$ back we get
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=-dfraclnleft(v+sqrt2right)sqrt2+dfraclnleft(v-sqrt2right)sqrt2+dfraclnleft(v+1right)2-dfraclnleft(v-1right)2
endequation
Undoing the change of variable $v = sqrt1 - u^2$, we get
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx=dfraclnleft(sqrt1-u^2+sqrt2right)sqrt2-dfraclnleft(sqrt1-u^2-sqrt2right)sqrt2-dfraclnleft(sqrt1-u^2+1right)2+dfraclnleft(sqrt1-u^2-1right)2
endequation
Undoing the other change of variable $u = tan (x)$, we get
beginequation
dfraclnleft(sqrt1-tan^2left(xright)+sqrt2right)sqrt2-dfraclnleft(sqrt1-tan^2left(xright)-sqrt2right)sqrt2-dfraclnleft(sqrt1-tan^2left(xright)+1right)2+dfraclnleft(sqrt1-tan^2left(xright)-1right)2
endequation
Now, depending where you're integrating, you've got to have absolute values in the arguments of the logarithms.






share|cite|improve this answer






















  • what is the mistake @RajeshGupta?
    – Ahmad Bazzi
    Aug 27 at 15:51












up vote
1
down vote










up vote
1
down vote









First notice that
beginequation
cosleft(2xright)=cos^2left(xright)-sin^2left(xright)
endequation
and
beginequation
sinleft(xright)=dfractanleft(xright)secleft(xright)
endequation
so
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleint
sec^2(x) cdotdfracsqrt1-tan^2left(xright)tanleft(xright)left(tan^2left(xright)+1right),mathrmdx
endequation
Change of variable as
beginequation
u = tan (x)
endequation
we get
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleintdfracsqrt1-u^2uleft(u^2+1right),mathrmdu
endequation
Another change of variable as
beginequation
v = sqrt1 - u^2
endequation
gives us
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=-displaystyleintdfracv^2left(v^2-2right)left(v^2-1right),mathrmdv
endequation
Now let's factor the denominator as
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleintdfracv^2left(v-1right)left(v+1right)left(v^2-2right),mathrmdv
endequation
Then perform partial fraction decomposition
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleintleft(dfrac2v^2-2+dfrac12left(v+1right)-dfrac12left(v-1right)right)mathrmdv
=
2A + frac12B - frac12 C
endequation
Let's do $A$,
beginequation
A = displaystyleintdfrac1v^2-2,mathrmdv
=
=displaystyleintdfrac1left(v-sqrt2right)left(v+sqrt2right),mathrmdv
=displaystyleintleft(dfrac12^frac32left(v-sqrt2right)-dfrac12^frac32left(v+sqrt2right)right)mathrmdv
endequation
which s
beginequation
A
=
=dfraclnleft(v-sqrt2right)2^frac32-dfraclnleft(v+sqrt2right)2^frac32
endequation
Now, similarly
beginequation
B =lnleft(v+1right)
endequation
and
beginequation
C =lnleft(v-1right)
endequation
Plugging all $A,B,C$ back we get
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=-dfraclnleft(v+sqrt2right)sqrt2+dfraclnleft(v-sqrt2right)sqrt2+dfraclnleft(v+1right)2-dfraclnleft(v-1right)2
endequation
Undoing the change of variable $v = sqrt1 - u^2$, we get
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx=dfraclnleft(sqrt1-u^2+sqrt2right)sqrt2-dfraclnleft(sqrt1-u^2-sqrt2right)sqrt2-dfraclnleft(sqrt1-u^2+1right)2+dfraclnleft(sqrt1-u^2-1right)2
endequation
Undoing the other change of variable $u = tan (x)$, we get
beginequation
dfraclnleft(sqrt1-tan^2left(xright)+sqrt2right)sqrt2-dfraclnleft(sqrt1-tan^2left(xright)-sqrt2right)sqrt2-dfraclnleft(sqrt1-tan^2left(xright)+1right)2+dfraclnleft(sqrt1-tan^2left(xright)-1right)2
endequation
Now, depending where you're integrating, you've got to have absolute values in the arguments of the logarithms.






share|cite|improve this answer














First notice that
beginequation
cosleft(2xright)=cos^2left(xright)-sin^2left(xright)
endequation
and
beginequation
sinleft(xright)=dfractanleft(xright)secleft(xright)
endequation
so
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleint
sec^2(x) cdotdfracsqrt1-tan^2left(xright)tanleft(xright)left(tan^2left(xright)+1right),mathrmdx
endequation
Change of variable as
beginequation
u = tan (x)
endequation
we get
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleintdfracsqrt1-u^2uleft(u^2+1right),mathrmdu
endequation
Another change of variable as
beginequation
v = sqrt1 - u^2
endequation
gives us
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=-displaystyleintdfracv^2left(v^2-2right)left(v^2-1right),mathrmdv
endequation
Now let's factor the denominator as
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleintdfracv^2left(v-1right)left(v+1right)left(v^2-2right),mathrmdv
endequation
Then perform partial fraction decomposition
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=displaystyleintleft(dfrac2v^2-2+dfrac12left(v+1right)-dfrac12left(v-1right)right)mathrmdv
=
2A + frac12B - frac12 C
endequation
Let's do $A$,
beginequation
A = displaystyleintdfrac1v^2-2,mathrmdv
=
=displaystyleintdfrac1left(v-sqrt2right)left(v+sqrt2right),mathrmdv
=displaystyleintleft(dfrac12^frac32left(v-sqrt2right)-dfrac12^frac32left(v+sqrt2right)right)mathrmdv
endequation
which s
beginequation
A
=
=dfraclnleft(v-sqrt2right)2^frac32-dfraclnleft(v+sqrt2right)2^frac32
endequation
Now, similarly
beginequation
B =lnleft(v+1right)
endequation
and
beginequation
C =lnleft(v-1right)
endequation
Plugging all $A,B,C$ back we get
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx
=-dfraclnleft(v+sqrt2right)sqrt2+dfraclnleft(v-sqrt2right)sqrt2+dfraclnleft(v+1right)2-dfraclnleft(v-1right)2
endequation
Undoing the change of variable $v = sqrt1 - u^2$, we get
beginequation
displaystyleintdfracsqrtcosleft(2xright)sinleft(xright),mathrmdx=dfraclnleft(sqrt1-u^2+sqrt2right)sqrt2-dfraclnleft(sqrt1-u^2-sqrt2right)sqrt2-dfraclnleft(sqrt1-u^2+1right)2+dfraclnleft(sqrt1-u^2-1right)2
endequation
Undoing the other change of variable $u = tan (x)$, we get
beginequation
dfraclnleft(sqrt1-tan^2left(xright)+sqrt2right)sqrt2-dfraclnleft(sqrt1-tan^2left(xright)-sqrt2right)sqrt2-dfraclnleft(sqrt1-tan^2left(xright)+1right)2+dfraclnleft(sqrt1-tan^2left(xright)-1right)2
endequation
Now, depending where you're integrating, you've got to have absolute values in the arguments of the logarithms.







share|cite|improve this answer














share|cite|improve this answer



share|cite|improve this answer








edited Aug 27 at 13:45

























answered Aug 27 at 13:39









Ahmad Bazzi

4,2861622




4,2861622











  • what is the mistake @RajeshGupta?
    – Ahmad Bazzi
    Aug 27 at 15:51
















  • what is the mistake @RajeshGupta?
    – Ahmad Bazzi
    Aug 27 at 15:51















what is the mistake @RajeshGupta?
– Ahmad Bazzi
Aug 27 at 15:51




what is the mistake @RajeshGupta?
– Ahmad Bazzi
Aug 27 at 15:51


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