【1】[x-3y]^2n-3[x-3y]^2x+1-2[3y-x]^2n+[3y-x]^2x+1的值,其中n为正整数,且x=2,y=1 【2】求8[2a+3b]^2-7[2a+3b]+2[2a+3b]^2-3[2a+3b]的值,其中a=2分

问题描述:

【1】[x-3y]^2n-3[x-3y]^2x+1-2[3y-x]^2n+[3y-x]^2x+1的值,其中n为正整数,且x=2,y=1 【2】求8[2a+3b]^2-7[2a+3b]+2[2a+3b]^2-3[2a+3b]的值,其中a=2分之1,b=-3分之2

【1】[x-3y]^2n-3[x-3y]^2x+1-2[3y-x]^2n+[3y-x]^2x+1的值=[x-3y]^2n-3[x-3y]^2x+1-2[x-3y]^2n-[x-3y]^2x+1=-4[x-3y]^2x+1-[x-3y]^2n=-4[2-3*1]^2*2+1-[2-3*1]^2n=-4*(-1)-1=3【2】求8[2a+3b]^2-7[2a+3b]+2[2a+3b]^2...