作业帮5*(x+4)-0.5*2=32 怎么解
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/06 01:40:16
5*(x+4)-0.5*2=32 怎么解
5*(x+4)-0.5*2=32 怎么解
5*(x+4)-0.5*2=32 怎么解
2.6
5*(x+4)-0.5*2=32
5*(x+4)-1=32
5*(x+4)=33
x+4=6.6
x=2.6
1.（X+2)^2+6(X+2)+8
=[(x+2)+2][(x+2)+4]
=(x+4)(x+6)
2.-x^4y+x^2y^2-xy( 注x^4指的是x的四次方）
=xy(-x³+xy-1)
3.x^2+x-4y^2-2y
=(x²-4y²)+(x-2y)
=(x-2y)(x+2y)+(x-2y)
全部展开
1.（X+2)^2+6(X+2)+8
=[(x+2)+2][(x+2)+4]
=(x+4)(x+6)
2.-x^4y+x^2y^2-xy( 注x^4指的是x的四次方）
=xy(-x³+xy-1)
3.x^2+x-4y^2-2y
=(x²-4y²)+(x-2y)
=(x-2y)(x+2y)+(x-2y)
=(x-2y)(x+2y+1)
4.x^2+2xy+y^2-(x+y)-6
=(x+y)²-(x+y)-6
=(x+y-3)(x+y+2)
5.a^4+0.25 (0.25即是四分之一）
=(a²+0.5)²-a²
=(a²+a+0.5)(a²-a+0.5)
6.(x^2+3x-3)(x^2+3x+4)-8
=(x²+3x)²+(x²+3x)-20
=(x²+3x+5)(x²+3x-4)
=(x²+3x+5)(x+4)(x-1)
7.x^4+x^2y^2+y^4
=(x²+y²)-x²y²
=(x²+y²+xy)(x²+y²-xy)
8.a^2(a-1)^2+32(a-a^2)+60
=[a(a-1)]²-32a(a-1)+60
=[a(a-1)-2][a(a-1)-30]
=(a-2)(a+1)(a-6)(a+5)
9.4x^2+12x-7
=(2x-1)(2x+7)
10.已知a-2b=5,3a+4b=6,求多项式3a^2-2ab-8b^2的值
3a²-2ab-8b²
=(3a+4b)(a-2b)
=6×5
=30
收起