题目
几道因式分解题要求助!
x^4+4x^3-12x-9
x^3-y^3-x^2-xy-y^2
a^8+a^4b^4+b^8
(a^2-1)(b^2-1)-4ab
麻烦给出过程和思路
x^4+4x^3-12x-9
x^3-y^3-x^2-xy-y^2
a^8+a^4b^4+b^8
(a^2-1)(b^2-1)-4ab
麻烦给出过程和思路
提问时间:2020-11-11
答案
x^4+4x³-12x-9,补回x²项
=x^4+4x³+3x²-3x²-12x-9
=x²(x²+4x+3)-3(x²+4x+3)
=(x²+4x+3)(x²-3)
=(x+1)(x+3)(x²-3)
=(x+1)(x+3)(x+√3)(x-√3)
x³-y³-x²-xy-y²,补回x²y项和xy²项
=x³+x²y+xy²-x²y-xy²-y³-x²-xy-y²
=x(x²+xy+y²)-y(x²+xy+y²)-(x²+xy+y²)
=(x-y-1)(x²+xy+y²)
a^8+(a^4)(b^4)+b^8,记得a²+b²=(a+b)²-2ab
=a^8+2(a^4)(b^4)+b^8-(a^4)(b^4)
=(a^4+b^4)²-(a²b²)²
=(a^4+b^4+a²b²)(a^4+b^4-a²b²)
=(a^4+2a²b²+b^4-a²b²)(a^4-a²b²+b^4)
=[(a²+b²)²-(ab)²](a^4-a²b²+b^4)
=(a²+b²-ab)(a²+b²+ab)(a^4-a²b²+b^4)
(a²-1)(b²-1)-4ab,拆开再重组
=a²b²-a²-b²-4a²+1
=a²b²-4ab-a²-b²+1
=a²b²-2ab+1-a²-2ab-b²
=a²b²-2ab+1-(a²+2ab+b²)
=(ab-1)²-(a+b)²
=[(ab-1)-(a+b)][(ab-1)+(a+b)]
=(ab-1-a-b)(ab-1+a+b)
=x^4+4x³+3x²-3x²-12x-9
=x²(x²+4x+3)-3(x²+4x+3)
=(x²+4x+3)(x²-3)
=(x+1)(x+3)(x²-3)
=(x+1)(x+3)(x+√3)(x-√3)
x³-y³-x²-xy-y²,补回x²y项和xy²项
=x³+x²y+xy²-x²y-xy²-y³-x²-xy-y²
=x(x²+xy+y²)-y(x²+xy+y²)-(x²+xy+y²)
=(x-y-1)(x²+xy+y²)
a^8+(a^4)(b^4)+b^8,记得a²+b²=(a+b)²-2ab
=a^8+2(a^4)(b^4)+b^8-(a^4)(b^4)
=(a^4+b^4)²-(a²b²)²
=(a^4+b^4+a²b²)(a^4+b^4-a²b²)
=(a^4+2a²b²+b^4-a²b²)(a^4-a²b²+b^4)
=[(a²+b²)²-(ab)²](a^4-a²b²+b^4)
=(a²+b²-ab)(a²+b²+ab)(a^4-a²b²+b^4)
(a²-1)(b²-1)-4ab,拆开再重组
=a²b²-a²-b²-4a²+1
=a²b²-4ab-a²-b²+1
=a²b²-2ab+1-a²-2ab-b²
=a²b²-2ab+1-(a²+2ab+b²)
=(ab-1)²-(a+b)²
=[(ab-1)-(a+b)][(ab-1)+(a+b)]
=(ab-1-a-b)(ab-1+a+b)
举一反三
已知函数f(x)=x,g(x)=alnx,a∈R.若曲线y=f(x)与曲线y=g(x)相交,且在交点处有相同的切线,求a的值和该切线方程.
我想写一篇关于奥巴马的演讲的文章,写哪一篇好呢?为什么好
奥巴马演讲不用看稿子.为什么中国领导演讲要看?
想找英语初三上学期的首字母填空练习……
英语翻译
最新试题
热门考点
- 1_ his great wisdom.he hesitated in face of the challenge
- 2一个正数x的平方根是2a-3与5-a.求a和x
- 3平方根概念
- 4甲 乙两个实心物体漂浮在水面上,体积之比为2比1,浸在水中部分的体积之比为1比2,那么它们的密度比是多少.
- 5我不怕辛苦用英语怎么说
- 6有一个0.1平方的水箱,要求温度控制在23-25度,该配多大的压缩机及冷凝器
- 7我成绩不是很好,80分吧英语90几,语文80几,是平常.我现在5年纪,考哪个初中好,
- 8Nancy goes to school ____a bus everyday
- 9在一块长80米的长方形场地一端修一个长方形游泳池剩下的是一个正方形游泳池的周长是?米
- 10在数字之间填上合适的运算符号:999 999 8 8 8 8 8 8=2001