y=f(x²) /x²那么y'= { [f(x²)]' *x² - f(x²) *(x²)'} / x^4显然[f(x²)]'=f '(x²) * (x²)'=2x *f '(x²),而(x²)'=2x于是y'= { [f(x²)]' *x² - f(x&...