已知函数f(x)=x三次方+ax平方+bx+c在x=负3分之2与x=1时都取得极值,求a.b的值

f(x)=x^3+ax^2+bx+c
f'(x)=3x^2+2ax+b
f(x)x=-2/3与x=1时都取得极值
==>f'(-2/3)=f'(1)=0
==>4/3-4/3a+b=0,3+2a+b=0
==>a=-1,b=-1