If y = x sinx, find dy/dx when x = π/2.
A
-π/2
B
-1
C
1
D
π/2
Verified Correct Answer: C.
Step-by-Step Mathematical Solution
y = x sin x
dy/dx = 1 x sinx + x cosx
= sinx + x cosx
At x = π/2, = sin (π/2) + (π/2) cos (π/2)
= 1 + (π/2) x (0) = 1
Source: Myschool Past Questions Archive (Record #2569)