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Radon222 (166)

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int  rac{3+2cosx}{(2+3cosx)^2},dx

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Greatdreams (3307)

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Multiplying numerator and deno by

cosec 2 x

we have,

(3 cosec 2 x + 2 cot x cosec x ) / ( 2 cosec x + 3 cot x ) 2

= - (- 3 cosec 2 x- 2 cot x cosec x)/(2 cosec x + 3 cot x ) 2

Now that becomes simple then and we have,

So I =   1/(2 cosec x +  3 cot x) = [sin x/ 2 + 3 cosec x] + c

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konichiwa2x (2373)

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edit: removed solution as per radon's request. Open for others to try
Another method:  Substitute

Guide to latex:
http://www.goiit.com/posts/list/community-shelf-a-guide-to-latex-48056.htm

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computer001 (1849)

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make given integral as
{(3+2cosx)/3sinx}d(1/2+3cosx)
apply parts
the integral trem comes out as
integarl[ {(2sin^2x+(3+2cosx)cosx)/sin^2x}*dx/(3+2cosx)]
= (3+2cosx/sin^2x)*dx/3+2cosx= cosec^2xdx
which is direct
ofcourse there will b some 1/3 or something outside as 1/3*integral..but thts all not important here

Nitwit Blubber Odment Tweak
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Radon222 (166)

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wow ! great attempts ....and really awesome substitution by konichiwa

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sandeepramesh (1247)

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yes that method is called integration by differentiation or sth :)
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