帮忙用提取公因式法解以下一元二次方程.① x^3+9+3x^2+3x ② -6x^2+7x+5 ③x^2-(a+b)xy+aby^2 ④2y^2-4y-6⑤ b^4-2b^2-8 ⑥-13ab^2x^6-39a^3b^2x^5

问题描述:

帮忙用提取公因式法解以下一元二次方程.
① x^3+9+3x^2+3x ② -6x^2+7x+5 ③x^2-(a+b)xy+aby^2 ④2y^2-4y-6
⑤ b^4-2b^2-8 ⑥-13ab^2x^6-39a^3b^2x^5

① x^3+9+3x^2+3x = x^2( x + 3)+ 3(x + 3 )=(x + 3 )(x^2+3)
② -6x^2+7x+5 =( -3x + 5 )( 2x + 1)
③x^2-(a+b)xy+aby^2=(x -ay)(x-by)
④2y^2-4y-6=2(y-3)(y+1)
⑤ b^4-2b^2-8 =(b^2-4)( b^2+2)=(b+2)(b-2)(b^2+2)
⑥-13ab^2x^6-39a^3b^2x^5= -13ab^2x^5(x+3a^2)

① x^3+9+3x^2+3x=x²(x+3)+3(x+3)=(x+3)(x²+3) ② -6x^2+7x+5=-(6x²-7x-5)=(3x-5)(x+1)③x^2-(a+b)xy+aby^2 =(x-ay)(x-by)④2y^2-4y-6=2(y²-2y-3)=2(y+1)(y-3)⑤ b^4-2b^2-8=(b²-4)(b²...