(很有难度、拜托啊):1)3x²+5xy-2y²+x+9y-4 2) 2x²+1)3x²+5xy-2y²+x+9y-42) 2x²+xy-y²-4x+5额、对不起啊。第二题打错了:2)2x²+xy-y²-4x+5y-6
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/23 17:49:41
![(很有难度、拜托啊):1)3x²+5xy-2y²+x+9y-4 2) 2x²+1)3x²+5xy-2y²+x+9y-42) 2x²+xy-y²-4x+5额、对不起啊。第二题打错了:2)2x²+xy-y²-4x+5y-6](/uploads/image/z/2519616-48-6.jpg?t=%EF%BC%88%E5%BE%88%E6%9C%89%E9%9A%BE%E5%BA%A6%E3%80%81%E6%8B%9C%E6%89%98%E5%95%8A%EF%BC%89%EF%BC%9A1%EF%BC%893x%26sup2%3B%EF%BC%8B5xy%EF%BC%8D2y%26sup2%3B%EF%BC%8Bx%EF%BC%8B9y%EF%BC%8D4+2%29+2x%26sup2%3B%EF%BC%8B1%EF%BC%893x%26sup2%3B%EF%BC%8B5xy%EF%BC%8D2y%26sup2%3B%EF%BC%8Bx%EF%BC%8B9y%EF%BC%8D42%29+2x%26sup2%3B%EF%BC%8Bxy%EF%BC%8Dy%26sup2%3B%EF%BC%8D4x%EF%BC%8B5%E9%A2%9D%E3%80%81%E5%AF%B9%E4%B8%8D%E8%B5%B7%E5%95%8A%E3%80%82%E7%AC%AC%E4%BA%8C%E9%A2%98%E6%89%93%E9%94%99%E4%BA%86%EF%BC%9A2%EF%BC%892x%26sup2%3B%EF%BC%8Bxy%EF%BC%8Dy%26sup2%3B%EF%BC%8D4x%EF%BC%8B5y%EF%BC%8D6)
(很有难度、拜托啊):1)3x²+5xy-2y²+x+9y-4 2) 2x²+1)3x²+5xy-2y²+x+9y-42) 2x²+xy-y²-4x+5额、对不起啊。第二题打错了:2)2x²+xy-y²-4x+5y-6
(很有难度、拜托啊):1)3x²+5xy-2y²+x+9y-4 2) 2x²+
1)3x²+5xy-2y²+x+9y-4
2) 2x²+xy-y²-4x+5
额、对不起啊。第二题打错了:
2)2x²+xy-y²-4x+5y-6
....我跪倒。
(很有难度、拜托啊):1)3x²+5xy-2y²+x+9y-4 2) 2x²+1)3x²+5xy-2y²+x+9y-42) 2x²+xy-y²-4x+5额、对不起啊。第二题打错了:2)2x²+xy-y²-4x+5y-6
3x²+5xy-2y²+x+9y-4
=3x²+5xy-2y²+4x-3x+8y+y-4
=(x+2y)(3x-y)+4x+8y-3x+y-4
=(x+2y)(3x-y)+4(x+2y)-(3x-y+4)
=(x+2y)(3x-y+4)-(3x-y+4)
=(x+2y-1)(3x-y+4)
2x²+xy-y²-4x+5y-6
=(2x-y)(x+y)+2x-6x+2y+3y-6
=(2x-y)(x+y)+2(x+y)-3(2x-y)-6
=(2x-y)(x+y-3)+2(x+y-3)
=(2x-y+2)(x+y-3)
3x²+5xy-2y²+x+9y-4
= (x+2y)(3x-y) + 4(x+2y)-(3x-y) -4
= (x+2y-1)(3x-y+4)
第二问有问题,
2x²+xy-y²-4x+5
= 2x²+(y-4)x-y²+5
令之为0, 得 x= 4-y±√...
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3x²+5xy-2y²+x+9y-4
= (x+2y)(3x-y) + 4(x+2y)-(3x-y) -4
= (x+2y-1)(3x-y+4)
第二问有问题,
2x²+xy-y²-4x+5
= 2x²+(y-4)x-y²+5
令之为0, 得 x= 4-y±√(y-4)²+8(y²-5) =4-y±√(9y²-8y-24)
根号下面的 9y²-8y-24 不是完全平方式,因此开不出来,所以原式无法因式分解。
收起
1)3x2+5xy-2y2+x+9y-4
=(3x-y+4)(x+2y-1)
2) 2x2+xy-y2-4x+5
就是设成2(x+ay+b)(x+cy+d) 死算……
但是仿佛无解。。。。。。
1111111111111111
你的第二题是不是应该是2xy啊??
1)3x²+5xy-2y²+x+9y-4=(x+2y-1)(3x-y+4)
2)错了吧!