Mathematics

Evaluate: $\displaystyle\int {{{\cos 2x} \over {\sin x}}dx}$

SOLUTION
$I=\displaystyle\int \dfrac{\cos 2x}{\sin x}dx$

$=\displaystyle\int \dfrac{1-2\sin^2x}{\sin x}dx$

$=\displaystyle\int cosec xdx-2\displaystyle\int \sin x dx$

$=log|cosec x+\cot x|+2\cos x+c$.

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Subjective Medium Published on 17th 09, 2020
Questions 203525
Subjects 9
Chapters 126
Enrolled Students 84

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