(x+1)^4=a0+a1x+a2x^2+a3x^3+a4x^4则a1+2a2+3a3+4a4的值?

问题描述:

(x+1)^4=a0+a1x+a2x^2+a3x^3+a4x^4则a1+2a2+3a3+4a4的值?

展开,有:a1=1,a2=4,a3=6,a4=4,a5=1,则a1+2a2+3a3+4a4=43.