8.(2023春•怀仁市期末)已知函数f(x)=(x−2)ex−a2x2+axf(x)=({x-2}){e^x}-\frac{a}{2}{x^2}+axf(x)=(x−2)ex−2ax2+ax,a∈Ra\in Ra∈R.(1)若a=0a=0a=0时,求f(x)f(x)f(x)在x=0x=0x=0处的切线方程;(2)讨论函数f(x)f(x)f(x)的单调性.