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计算3x/(x-3y)+(x+y)/(4y-x)-7y/(x-4y)=?

来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/11/08 14:48:46
计算3x/(x-3y)+(x+y)/(4y-x)-7y/(x-4y)=?
前面你看下是 X-3Y 还是X-4Y
3x/(x-3y)+(x+y)/(4y-x)-7y/(x-4y)
=3x/(x-3y)-(x+y)/(x-4y)-7y/(x-4y)
=3x(x-3y)-(x+y-7y)/(x-4y)
=3x(x-3y)-(x-6y)/(x-4y)

3x/(x-4y)+(x+y)/(4y-x)-7y/(x-4y)
=3x/(x-4y)-(x+y)/(x-4y)-7y/(x-4y)
=(3x-x-y-7y)/(x-4y)
=(2x-8y)/(x-4y)=2