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
问题描述:
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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答
(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)4...将(a-b)^2+2(a-b)-3进行因式分解因式分a^2b^2-15ab+36(a-b)^2+2(a-b)-3=(a-b+3)(a-b-1) a^2b^2-15ab+36=(ab-3)(ab-12)