救命,全是因式分解.1.(x-3)^2+8(x-3)+162.3m^2-6mn+3n^23.x^4-164.2x^4-1
2个回答

1.=(x-3+4)^2=(x+1)^2

2.=3(m^2-2mn+n^2)=3(m-n)^2

3.=(x^2+4)(x^2-4)=(x^2+4)(x+2)(x-2)

4.=2(x^4-8x^2+16)=2(x^2-4)^2=2(x+2)^2(x-2)^2

5.=(X-2)(X^2+2X+4)

6=3(X^3+8)=3(x+2)(X^2-2x+4)

7=a^2-(b^2-2bc+c^2)=a^2-(b-c)^2=(a+b-c)(a-b+c)

8=(a+B+C)^3

9=(3(x-y)-4)^2

10=(a-b-c)^2

11=(2x-2(y-1))^2

12=a^2-a-a^3+a^2=a(a-1)-a^2(a-1)=(a-1)(a-a^2)=-a(a-1)^2

13=3a(x+y)(x-y)

14=-4a(4a^2-4ab+b^2)=-4a(2a-b)^2

15=(y^2-1)(x^2-1)=(y+1)(y-1)(X+1)(x-1)