括号x加1乘以括号x加3乘以括号x加5乘以括号x加7减20
问题描述：
括号x加1乘以括号x加3乘以括号x加5乘以括号x加7减20
答
原式=[(x+1)(x+7)][(x+3)(x+5)]-20=(x^2+8x+7)(x^2+8x+15)-20=(x^2+8x+7)^2+8(x^2+8x+7)-20=(x^2+8x+7+10)(x^2+8x+7-2)=(x^2+8x+17)(x^2+8x+5)手机提问的朋友在客户端右上角评价点【满意】即可....