Engineering Board Exam Reviewer · Derivatives of Algebraic Functions · hard
Find y' if y=(x2-3)4(2x+1)2.
4(x2-3)3(2x+1)(5x2+2x-3)
8x(x2-3)3(2x+1)2
4(x2-3)4(2x+1)
(x2-3)3(2x+1)(5x2+2x-3)
Answer
A. 4(x2-3)3(2x+1)(5x2+2x-3)
Solution
By the product rule with u=(x2-3)4, v=(2x+1)2: u'=8x(x2-3)3, v'=4(2x+1). Then y'=8x(x2-3)3(2x+1)2+4(2x+1)(x2-3)4, which factors to 4(x2-3)3(2x+1)(5x2+2x-3).