Question

因式分解：(1)3a^4-8a^2-16 (2)2x^3-x^2-15x (3)3x^2-10x-8 (4)2x^2+x-15 (5)6x^2-11x=3 （6）4x^2+5x-6

(7)6x^2-17x+10 (8)-8x^2+6x+9
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Answer 1

(1)3a^4-8a^2-16
=（3a²+4)(a²-4)
=（3a²+4)(a+2)(a-2)

(2)2x^3-x^2-15x
=x(2x²-x-15)
=x(2x+5)(x-3)

(3)3x^2-10x-8
=(3x+2)(x-4)

(4)2x^2+x-15
=(2x-5)(x+3)

(5)6x^2-11x+3
=(2x-3)(3x-1)

（6）4x^2+5x-6
=(4x-3)(x+2)

(7)6x^2-17x+10
=(6x-5)(x-2)

(8)-8x^2+6x+9
=-(8x²-6x-9)
=-(2x-3)(4x+3)

追问

将(a-b)^2+2(a-b)-3进行因式分解

因式分解：a^2b^2-15ab+36

追答

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

a^2b^2-15ab+36=(ab-3)(ab-12)

Answer 2

3a^4-8a^2-16
=(3a^2+4)(a^2-4)
=(3a^2+4)(a+2)(a-2)

2x^3-x^2-15x
=x(2x^2-x-15)
=x(2x+5)(x-3)

3x^2-10x-8
=(3x+2)(x-4)
=(3x+2)(x+2)(x-2)

2x^2+x-15
=(2x-5)(x+3)

6x^2-11x+3
=(2x-3)(3x-1)

4x^2+5x-6
=(4x-3)(x+2)

6x^2-17x+10
=(x-2)(6x-5)

-8x^2+6x+9
=(-2x+3)(4x+3)

Answer 3

3a^4-8a^2-16
=(a-4)(3a+4)

2x^3-x^2-15x
=x(2x^2-x-15)
=x(x-3)(2x+5)

3x^2-10x-8
=(3x+2)(x-4)

2x^2+x-15
=(x+3)(2x-5)

6x^2-11x+3
=(2x-3)(3x-1)

4x^2+5x-6
=(4x-3)(x+2)

6x^2-17x+10
=(6x-5)(x-2)

-8x^2+6x+9
=(-2x+3)(4x+3)