1.f(x) = x的sinx/x次方 , then f′(pi) =
2.Suppose g is the inverse function of a differentiable function f and letG(x) = 1/g(x) If f(3) = 2 and f′(3) = 1/9, then G′(2) =
3.f(x) = ax的3次方 + bx的2次方 + cx + d has a relative maxima value of 3 at −2 and a relative
minima value of 0 at −1, then a + b + c + d =