19. (2023春•泸县校级期末)已知函数f(x)=13x3−x2+1f(x)=\frac{1}{3}{x}^{3}-{x}^{2}+1f(x)=31x3−x2+1.求:(1)曲线y=f(x)y=f(x)y=f(x)在点(1(1(1,fff(1))))处的切线方程;(2)函数y=f(x)y=f(x)y=f(x)在区间[−2[-2[−2,3]3]3]上的最值.