中科新闻网胎儿32周羊水多少正常:因式分解
来源：百度文库 编辑：中科新闻网 时间：2024/04/29 03:41:37
2x^2-1/2y^2
49(a-b)^2-16(a+b)^2
49(a-b)^2-16(a+b)^2
2x^2-1/2y^2
=2(x^2-1/4y^2 )
=2(x+1/2y)(x-1/2y)
49(a-b)^2-16(a+b)^2
=[7(a-b)+4(a+b)][7(a-b)-4(a+b)]
(11a-3b)(3a-11b)
看不懂呀
2x^2-1/2y^2 =1/2(4x^2-y^2)=1/2(2x+y)(2x-y)
49(a-b)^2-16(a+b)^2
=[7(a-b)+4(a+b)][7(a-b)-4(a+b)]
=(11a-3b)(3a-11b)