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因式分解:①axˆ2-16ayˆ2②-xˆ2+2xy-yˆ2③aˆ2-2ab+bˆ2-1④(x+y)ˆ2-10(x+y)+25⑤xˆ2y-9y⑥xˆ2+6x+9⑦mˆ3-4m⑧2mxˆ2-4mx+2m⑨9xˆ2-yˆ2-4y-4⑨(x+y)ˆ2-3(x+

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因式分解:①axˆ2-16ayˆ2 ②-xˆ2+2xy-yˆ2 ③aˆ2-2ab+bˆ2-1 ④(x+y)ˆ2-10(x+y)+25 ⑤xˆ2y-9y ⑥xˆ2+6x+9 ⑦mˆ3-4m ⑧2mxˆ2-4mx+2m ⑨9xˆ2-yˆ2-4y-4 ⑨(x+y)ˆ2-3(x+y)⑩若3aˆ2-a-2=0,则5+2a-6aˆ2 解方程:(3y-1)ˆ2=(y-3)ˆ2 化简并求值:[(3a-7)ˆ2-(a+5)ˆ2]÷(4a-24),其中a=3/8 简单应用题:①(2a+2b-1)(2a+2b+1)=35,试求代数式a+b的值 ②已知:x=根号3+1,y=根号3-1 求下列各值.(1)xˆ2+2xy+yˆ2 (2)xˆ2-yˆ2 ③已知x-1=根号3,求代数式(x+1)ˆ2-4(x+1)+4 【题量很多,各位不着急慢慢做,正确率尽量高一些.在这里谢过各位仁兄.】
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答案和解析
①axˆ2-16ayˆ2 =a(x-4y)(x+4y)
②-xˆ2+2xy-yˆ2=-(x-y)²
③aˆ2-2ab+bˆ2-1=(a-b)²-1=(a-b-1)(a-b+1)
④(x+y)ˆ2-10(x+y)+25=(x+y-5)²
⑤xˆ2y-9y=y(x-3)(x+3)
⑥xˆ2+6x+9=(x+3)²
⑦mˆ3-4m=m(m+2)(m-2)
⑧2mxˆ2-4mx+2m=2m(x-1)²
⑨9xˆ2-yˆ2-4y-4=(3x-y-2)(3x+y+2)
⑨(x+y)ˆ2-3(x+y)=(x+y)(x+y-3)
⑩若3aˆ2-a-2=0,则5+2a-6aˆ2 =1
解方程:(3y-1)ˆ2=(y-3)ˆ2 y=1or-1
化简并求值:[(3a-7)ˆ2-(a+5)ˆ2]÷(4a-24),其中a=3/8 原式=4(a-6)(2a-1)÷4(a-6)=2a-1=-1/4
简单应用题:①(2a+2b-1)(2a+2b+1)=35,试求代数式a+b的值
由原式可知:4(a+b)²-1=35;所以a+b=3
②已知:x=根号3+1,y=根号3-1 求下列各值.
(1)xˆ2+2xy+yˆ2 =(x+y)²=12
(2)xˆ2-yˆ2 =(x+y)(x-y)=4倍根号3
③已知x-1=根号3,求代数式(x+1)ˆ2-4(x+1)+4=(x+1-2)²=3
应该都对