问题描述: 解方程:(x+1)(x+3)(x+5)(x+7)+15=0 1个回答 分类:数学 2014-11-06 问题解答: 我来补答 [(x+1)(x+7)][(x+3)(x+5)]+15=0[(x²+8x)+7][(x²+8x)+15]+15=0(x²+8x)²+22(x²+8x)+105+15=0(x²+8x)²+22(x²+8x)+120=0(x²+8x+10)(x²+8x+12)=0(x²+8x+10)(x+2)(x+6)=0x=-4-2√6,x=-4+2√6,x=-2,x=-6 展开全文阅读