Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Definite Integration

Question:

$\int\limits_{0}^{2\pi} \text{cosec}^7 x \, dx =$

Options:

0

1

4

$2\pi$

Correct Answer:

0

Explanation:

The correct answer is Option (1) → 0

We know, $\int\limits_{0}^{2a} f(x) dx = 0$, if $f(2a-x) = -f(x)$

Let $f(x) = \text{cosec}^7 x$.

Now, $f(2\pi - x) = \text{cosec}^7(2\pi - x)$

$= -\text{cosec}^7 x = -f(x)$

$∴\int\limits_{0}^{2\pi} \text{cosec}^7 x \, dx = 0$