Thread: Derivative

1. If dy/dx = 2xy, then d²y/dx² =
(a) 2y
(b) 2x + 2y
(c) 2x + 4y
(d) 2x²y + 2y
(e) 4x²y + 2y

help me thanks ^^

Originally Posted by tmd

1. If dy/dx = 2xy, then d²y/dx² =
(a) 2y
(b) 2x + 2y
(c) 2x + 4y
(d) 2x²y + 2y
(e) 4x²y + 2y

help me thanks ^^

It's e).

dy/dx = 2xy

d^2y/dx^2 = (d/dx)(2xy) = 2y + 2x(dy/dx)

But dy/dx = 2xy

d^2y/dx^2 = 2y + 2x(dy/dx) = 2y + 2x(2xy) = 2y + 4x^2y

-Dan