分解下列因式:1.x^-2x-1 2.4(x-y+1)+y(y-2x) 3.a^3+1 4.4x^4-13x^+9 5.b^+c^+2ab+2ac+2bc 6.3x^+5xy-2y
问题描述:
分解下列因式:1.x^-2x-1 2.4(x-y+1)+y(y-2x) 3.a^3+1 4.4x^4-13x^+9 5.b^+c^+2ab+2ac+2bc 6.3x^+5xy-2y
分解下列因式:
1.x^-2x-1
2.4(x-y+1)+y(y-2x)
3.a^3+1
4.4x^4-13x^+9
5.b^+c^+2ab+2ac+2bc
6.3x^+5xy-2y^+x+9y-4
7.x^-二根号二x-3
8.3x^+4xy-y^
9.(x^-2x)^-7(x^-2x)+12
10.x^+x-(a^-a)
答
1题目是x^2-2x-1吧?令x^2-2x-1=0x1=1+√2 x2=1-√2x^2-2x-1=(x-x1)(x-x2)=(x-1-√2)(x-1+√2)2..4(x-y+1)+y(y-2x)=y^2-4y+4+4x-2xy=(y-2)^2+2x(2-y)=(y-2)(y-2x-2)3..a^3+1=(a+1)(a^2-a+1)4..4x^4-13x^+9=(x^2-1)(...谢谢谢谢~