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WBJEE · Maths · Definite Integration

The value of \(\int_0^{\infty} \frac{d x}{\left(x^2+4\right)\left(x^2+9\right)}\) is

  1. A \(\frac{\pi}{60}\)
  2. B \(\frac{\pi}{20}\)
  3. C \(\frac{\pi}{40}\)
  4. D \(\frac{\pi}{80}\)
Verified Solution

Answer & Solution

Correct Answer

(A) \(\frac{\pi}{60}\)

Step-by-step Solution

Detailed explanation

\begin{aligned} & \text { Hints : } \left.\int_0^{\infty} \frac{\mathrm{dx}}{\left(\mathrm{x}^2+4\right)\left(\mathrm{x}^2+9\right)}=\int_0^{\pi / 2} \frac{\sec ^2 \theta}{\left(\tan ^2 \theta+4\right)\left(\tan ^2 \theta+9\right)} \mathrm{d} \theta \text { (putting }…