Question

Co-ordinates of a point on the curve y = x log x at which the normal is parallel to the line 2x - 2y = 3 are
[RPET 2000]

• A. $(O_2,O)$
• B. (e, e)
• C. $(e^2,2e^2)$
• D. $(e^{-2},2e^{-2})$

Answer 1

The correct option is B (e, e)

$\frac{d}{dx}\left[f\right(sinx\left)\right]=\frac{d}{dx}\left[log\right(sinx\left)\right]=\frac{1}{sinx}.cosx=cotx.$