ExamBro
ExamBro
TS EAMCET · Maths · Definite Integration

If \(f(x, y)=\frac{\cos (x-4 y)}{\cos (x+4 y)}\), then \(\left.\frac{\partial f}{\partial x}\right|_{y=\frac{x}{2}}\) is equal to :

  1. A -1
  2. B 0
  3. C 1
  4. D 2
Verified Solution

Answer & Solution

Correct Answer

(B) 0

Step-by-step Solution

Detailed explanation

\(\because \quad f(x, y)=\frac{\cos (x-4 y)}{\cos (x+4 y)}\) \(\therefore \quad f\left(x, \frac{\pi}{2}\right)=\frac{\cos (x-2 \pi)}{\cos (x+2 \pi)}\) \(=\frac{\cos (2 \pi-x)}{\cos (2 \pi+x)}=\frac{\cos x}{\cos x}=1\) \(\therefore \quad \frac{\partial f}{\partial x}=0\)
From TS EAMCET
Explore more questions on app