1.x^2-4ax+8ab-4b^22.(a+b)(a-b)-ab-b^23.(ax+by)^2+(ay-6x)^24.x^2-xy-1+4分之1y^25.a^nb^(n+1)+a^n+b6.c^2+4ab-(a+b)^27.(x^2-x)^2-14(x^2-x)+248.(x^2+3x+1)^2+2(x^2+3x+1)-89.x^4-10x^2+25

Question

1.x^2-4ax+8ab-4b^2
2.(a+b)(a-b)-ab-b^2
3.(ax+by)^2+(ay-6x)^2
4.x^2-xy-1+4分之1y^2
5.a^nb^(n+1)+a^n+b
6.c^2+4ab-(a+b)^2
7.(x^2-x)^2-14(x^2-x)+24
8.(x^2+3x+1)^2+2(x^2+3x+1)-8
9.x^4-10x^2+25

Answer 1

1.x²-4ax+8ab-4b²
=x²-4b²-4ax+8ab
=(x-2b)(x+2b)-4a(x-2b)
=(x-b)(x+2b-4a)
2.(a+b)(a-b)-ab-b²
=a²-b²-ab-b²
=a²-ab-2b²
=(a-2b)(a+b)
3.(ax+by)²+(ay-bx)²(怀疑你题抄错了,后面的括号里是bx吧,不是6x)
=a²x²+b²y²+2abxy+a²y²+b²x²-2abxy
=a²x²+b²y²+a²y²+b²x²
=a²(x²+y²)+b²(x²+y²)
=(x²+y²)(a²+b²)
4.x²-xy-1+y²/4
=(x-y/2)²-1
=(x- y/2 -1)(x- y/2 +1)
6.c²+4ab-(a+b)²
=c²+4ab-a²-b²-2ab
=c²-(a-b)²
=(c+a-b)(c-a+b)
7.(x²-x)²-14(x²-x)+24
=(x²-x-2)(x²-x-12)
=(x+1)(x-2)(x+3)(x-4)
8.(x²+3x+1)²+2(x²+3x+1)-8
=(x²+3x+1+4)(x²+3x+1-2)
=(x²+3x+5)(x²+3x-1)
9.x^4-10x²+25
=(x²-5)²
=(x-5)²(x+5)² .