Question

Let q(x)=(x^4)(e^-x). Calculate q'(x). Use q'(x) to determine whether q(5)<q(6) or q(5)>q(6) (do not use a calculator). Explain your reasoning.

Answer 1

let q=uv

then q'=uv'+vu'

u= x^4 then u'=4x^3
v=e^-x then v'=-e^-x