如图,第答案错了吧?第3题!
(3)
f(x) =x^2 -∫(0->x^2) cos(t^2) dt
f'(x)
= 2x - 2x.cos(x^4)
=2x -2x. [ 1- (1/2)x^8 +o(x^8) ]
=x^9 +o(x^9)
g(x) = (sinx)^9 =x^9 +o(x^9)
f'(x), g(x) 是等价于 x^9
ans :A
真棒!