帮因式分解谢谢,4(x+y)(x-y)^3-9(x+y)^3(x-y) 9x^2-x+1/16这两题,4(x+y)(x-y)^3-9(x+y)^3(x-y)————————————————————————9x^2-x+1/16
来源：学生作业帮助网 编辑：六六作业网 时间：2024/11/27 16:01:32
帮因式分解谢谢,4(x+y)(x-y)^3-9(x+y)^3(x-y) 9x^2-x+1/16这两题,4(x+y)(x-y)^3-9(x+y)^3(x-y)————————————————————————9x^2-x+1/16
帮因式分解谢谢,4(x+y)(x-y)^3-9(x+y)^3(x-y) 9x^2-x+1/16这两题,
4(x+y)(x-y)^3-9(x+y)^3(x-y)
————————————————————————
9x^2-x+1/16
帮因式分解谢谢,4(x+y)(x-y)^3-9(x+y)^3(x-y) 9x^2-x+1/16这两题,4(x+y)(x-y)^3-9(x+y)^3(x-y)————————————————————————9x^2-x+1/16
4(x+y)(x-y)^3-9(x+y)^3(x-y)
=(x＋y)(x－y)[4(x－y)²－9(x＋y)²]
=(x＋y)(x－y){[2(x－y)]²－[3(x＋y)]²}
=(x＋y)(x－y)[(2x－2y)²－(3x＋3y)²]
=(x＋y)(x－y)(2x－2y＋3x＋3y)(2x－2y－3x－3y)
=(x＋y)(x－y)(5x＋y)(﹣x－5y)
=﹣(x＋y)(x－y)(5x＋y)(x＋5y)
方程9x^2-x+1/16=0的判别式为：
(﹣1)²－4×9×1／16＜0
所以原式在实数范围内不能分解因式
不懂还可问,o(∩_∩)o
原式=(x＋y)(x－y)[4(x－y)²－9(x＋y)²] =(x＋y)(x－y){[2(x－y)]²－[3(x＋y)]²} =(x＋y)(x－y)[(2x－2y)²－(3x＋3y)²] =(x＋y)(x－y)(2x－2y＋3x＋3y)(2x－2y－3x－3y) =(x＋y)(x－y)(5x＋y)(﹣x－5y) =﹣(x＋y)(x－y)...
全部展开
原式=(x＋y)(x－y)[4(x－y)²－9(x＋y)²] =(x＋y)(x－y){[2(x－y)]²－[3(x＋y)]²} =(x＋y)(x－y)[(2x－2y)²－(3x＋3y)²] =(x＋y)(x－y)(2x－2y＋3x＋3y)(2x－2y－3x－3y) =(x＋y)(x－y)(5x＋y)(﹣x－5y) =﹣(x＋y)(x－y)(5x＋y)(x＋5y) 方程9x^2-x+1/16=0的判别式为： (﹣1)²－4×9×1／16＜0 故原式在实数范围内不能分解因式。
收起
一楼是正确的