这个是定积分。
∫(0,1)(e^x-ax)^2dx
=∫(0,1)(e^2x-2axe^x+a^2x^2)dx
=∫(0,1)e^2xdx-2a∫(0,1)xe^xdx+a^2∫(0,1)x^2dx
=(1/2)∫(0,1)e^2xd2x-2a∫(0,1)xde^x+a^2∫(0,1)x^2dx
=(1/2)e^2x(0,1)-2axe^x(0,1)+2a∫(0,1)e^xdx+(a^2/3)x^3(0,1)
=(1/2)(e^2-1)-2ae+2ae^x(0,1)+(a^2/3)
=(1/2)(e^2-1)-2ae+2ae-2a+(a^2/3)
=(1/2)(e^2-1)-2a+(a^2/3)
详解