(2)(-x)^6÷(-x)^2×(-x)^3=x^6÷x^2×-x^3=-x

(3) 27x^8÷3x^4 =9x^4=(3x^2)^2

⑷- 12m^3n^3÷4m^2n^3=-3m

(5)(6x^2y^3z^2)^2÷4x^3y^4=36x^4y^6z^4÷4x^3y^4=9xy^2z^4

(6)(-6a^2b^5c)÷(-2ab^2)^2=(-6a^2b^5c)÷(4a^2b^4)=-3bc/2

(7)(6a^4-4a^3-2a^2)÷(-2a^2)=2a^2(3a^2-2a- 1)÷(-2a^2)= 1+2a-3a^2

(8)(4x^3y+6x^2y^2-xy^3)÷2xy=xy(4x^2+6xy-y^2)÷2xy=(4x^2+6xy-y^2)/2

(9)(x^4+2x^3- 1/2x^2)÷(- 1/2x)^2=x^2(x^2+2x- 1/2)*(4x^2)=x^4(2x^2+4x- 1)

( 10)(2ab^2-b^3)^2 ÷2b^3 =[b^2(2a-b)]^2÷2b^3=b^4(2a-b)÷2b^3=(2a-b)b/2

( 1 1){(x-2y)^2+(x-2y)(x+2y)-2x(2x-y)}÷2x=[x^2-4xy+4y^2+x^2-4y^2-4x^2+2xy]÷2x=[-2x^2-2xy]÷2x=-x-y

Decomposition factor

( 1)x^2-25x =(x-25)x

(2) 2x 2y 2-4y 3z = 2y 2 (x 2-2yz

(3)am-an+ap=a(m-n+p)

(4)x^3-25x=x(x^2-25)=x(x+5)(x-5)

(5) 1-4x^2=( 1-2x)( 1+2x)

(6) 25x^2+20xy+4y^2=(5x+2y)^2

First solve, then evaluate:

(1) 3a (2a 2-4a+3)-2a 2 (3a+4), where a=-2.

3a(2a^2-4a+3)-2a^2(3a+4)=6a^3- 12a^2+9a-6a^3-8a^2=a(-20a+9)

Where a=-2, brought into the equation, a(-20a+9)=-2[-20 *(2)+9]=-98.

(2) (a-3b) 2+(3a+b) 2-(a+5b) 2+(a-5b) 2, where a =-8 and b =-6.

(a-3b)^2+(3a+b)^2-(a+5b)^2+(a-5b)^2=a^2-6b+9b^2+9a^2+6b+b^2+(a-5b+a+5b)(a-5b-a-5b)= 10a^2+ 10b^2+2a(- 10b)= 10a^2-20ab+ 10b^2= 10(a-b)^2

Where a=-8 and b=-6, brought into the equation,10 (a-b) 2 =10 (-8+6) =-20.

It's so hard, haha, but the score is too small, hehe