matlab 求函数的极值点和拐点答:function hh global dy1 dy2 y='x^2*sin(x^2-x-2)'dy1=diff(y)dy2=diff(y,2)subplot(3,1,1)ezplot(y,[-2 2])subplot(3,1,2)ezplot(dy1,[-2 2]),hold on,plot(-2:2,zeros(length(-2:2)))subplot(3,1,3)ezplot(dy2,[-2 2]),hold on,plot(-2:2,zeros(length(...