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,
问题描述:
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
答
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