函数f(x)=(1/4)x⁴-(2/3)x³+(1/2)x²的所有极值点与零点之和为令f'(x)=x³-2x²+x=x(x²-2x+1)=x(x-1)²=0,得极值点x₁=0,x₂=1；再令f(x)=(1/4)x⁴-(2/3)x³+(1/...