16-24(X-1)+9( X-1)²怎么算
问题描述:
16-24(X-1)+9( X-1)²怎么算
答
16-24(x-1)+9(x-1)²
=4²-2·4·3(x-1)+[3(x-1)]²
=[4-3(x-1)][4+3(x-1)]
=(7-3x)(1+3x)【去括号的话就是:49-42x+9x²】