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shiva.raj (0)

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Find the value of the following integral


    
vnkt.swaroop (317)

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ankitagg (302)

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just put


cos x =(1-tan^2 x/2) / (1+tan^2 x/2)


u will get




(1+tan^2 x/2 ) (5+tan^2 x/2) / ((5-tan^2 x/2)


put tan x/2=t


then


1/2 [ (5+t^2) / (5-t^2) ]dt


u will easily now get the answer


edited.

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vnkt.swaroop (317)

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ankitagg in the numerator you will get 5+tan(x/2)^2.


now you will get 5+t^2/5-t^2

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deedee (1932)

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put tan(x/2) =t


thus x=tan inverse of (t)


dx=2/(1+t^2)


nw d q turns out 2 b ..............


solvin it u get.................


nw rite .............


thus get ........................


so first part bcums................... u can easily integrate it :)


for d second part put t=(root 5)*siny '


thus dt=(root 5)*cosy dy


thus ur integral seond part reduces to ......................here y = dy last mein hai na woh .....


this =................


nw multiply and divide by sin y


u get ......................... here this equation is diveided by 25


nw put tany =z thus sec^2 y dy=dz


nw u get .................


nw u can write it as.........


cancellin d first term u can intergrate it easily nw


note: d answer u get multiply it by (-1) coz remeber we had taken that .......sumwer in d first part......


hope it helps



don't walk as if u rule d world
walk as if u dont care who rules d world

-this is knw as attitude


B who u r and say wat u feel ......
coz those who mind don't matter ........
and those who matter dont mind ......... :)


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mukulss (493)

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gud wrk both.......

this word is so small that it is a foolishness to hate anyone.
so, we love all.
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deedee (1932)

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solly................................................................................................................................................................................................ 4 those bigggggggg spaces in betwn wich makes it difficult 2 read that  solution .bt that sol is perfect ........


don't walk as if u rule d world
walk as if u dont care who rules d world

-this is knw as attitude


B who u r and say wat u feel ......
coz those who mind don't matter ........
and those who matter dont mind ......... :)


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smith.greme (9)

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Sir, please solve this one.not getting satisfactory answer

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smith.greme (9)

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Hey , anyone please explain it nicely

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smith.greme (9)

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no one in goiit to explain this question???????????????????????????????????????????

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allamraju (3422)

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Deedee might be correct but here's a more simpler method.

Write the nr 3+2cosx=3(sin2x+cos2x)+2cosx=3sin2x+cosx(2+3cosx).Substituting this,the integrand becomes

3sin2x/(2+3cosx)2+cosx/2+3cosx

=(sinx)(1/2+3cosx)'+(1/2+3cosx)(sinx)'

=[sinx/2+3cosx]' whose integral is [sinx/(2+3cosx)]+c.

Hope you got it.

MAKING A MISTAKE IS HUMAN BUT REPEATING IT IS IDIOTIC.
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