计算:1、(xy分之x²-y²)×(x-y分之x)-(y分之x);2、6xy²-9x²y-y³(解方程);3、[(a²-4a+4分之a-1)-(a²-2a分之a+2)]÷(a分之4)-(1)
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/05 13:03:42
![计算:1、(xy分之x²-y²)×(x-y分之x)-(y分之x);2、6xy²-9x²y-y³(解方程);3、[(a²-4a+4分之a-1)-(a²-2a分之a+2)]÷(a分之4)-(1)](/uploads/image/z/197892-36-2.jpg?t=%E8%AE%A1%E7%AE%97%3A1%E3%80%81%28xy%E5%88%86%E4%B9%8Bx%26%23178%3B-y%26%23178%3B%29%C3%97%28x-y%E5%88%86%E4%B9%8Bx%29-%28y%E5%88%86%E4%B9%8Bx%29%EF%BC%9B2%E3%80%816xy%26%23178%3B-9x%26%23178%3By-y%26%23179%3B%EF%BC%88%E8%A7%A3%E6%96%B9%E7%A8%8B%EF%BC%89%EF%BC%9B3%E3%80%81%5B%28a%26%23178%3B-4a%2B4%E5%88%86%E4%B9%8Ba-1%29-%28a%26%23178%3B-2a%E5%88%86%E4%B9%8Ba%2B2%29%5D%C3%B7%EF%BC%88a%E5%88%86%E4%B9%8B4%EF%BC%89-%EF%BC%881%EF%BC%89)
计算:1、(xy分之x²-y²)×(x-y分之x)-(y分之x);2、6xy²-9x²y-y³(解方程);3、[(a²-4a+4分之a-1)-(a²-2a分之a+2)]÷(a分之4)-(1)
计算:1、(xy分之x²-y²)×(x-y分之x)-(y分之x);
2、6xy²-9x²y-y³(解方程);
3、[(a²-4a+4分之a-1)-(a²-2a分之a+2)]÷(a分之4)-(1)
计算:1、(xy分之x²-y²)×(x-y分之x)-(y分之x);2、6xy²-9x²y-y³(解方程);3、[(a²-4a+4分之a-1)-(a²-2a分之a+2)]÷(a分之4)-(1)
1、(xy分之x²-y²)×(x-y分之x)-(y分之x);
=(x+y)(x-y)/xy ×x/(x-y) -x/y
=(x+y)/y-x/y
=(x+y-x)/y
=1
2、6xy²-9x²y-y³(解方程);
=-y(9x²-6xy+y²)
=-y(3x-y)²
3、[(a²-4a+4分之a-1)-(a²-2a分之a+2)]÷(a分之4-1)
=[(a-1)/(a-2)² -(a+2)/a(a-2)]×a/(4-a)
=[a(a-1)-(a+2)(a-2)] /a(a-2)² ×a/(4 -a)
=(4-a)/a(a-2)² ×a/(4 -a)
=1/(a-2)²
=1/(a²-4a+4)
解
[(x²-y²)/xy]×[x/(x-y)]-(x/y)
=[(x-y)(x+y)/xy]×x/(x-y)-(x/y)
=(x+y)/y-(x/y)
=x/y+1-x/y
=1
6xy²-9x²y-y³
=-y(y²-6xy+9x²)
=-y(y-3x)²
[(a-1)/(a²-4a+4)-(a+2)/(a²-2a)]÷(4/a)-1——是这个吗?