已知m/n=5/3,求m/(m+n)+m/(m-n)-n平方/(m平方-n平方)
来源:学生作业帮助网 编辑:六六作业网 时间:2024/12/22 14:50:55
已知m/n=5/3,求m/(m+n)+m/(m-n)-n平方/(m平方-n平方)已知m/n=5/3,求m/(m+n)+m/(m-n)-n平方/(m平方-n平方)已知m/n=5/3,求m/(m+n)+m
已知m/n=5/3,求m/(m+n)+m/(m-n)-n平方/(m平方-n平方)
已知m/n=5/3,求m/(m+n)+m/(m-n)-n平方/(m平方-n平方)
已知m/n=5/3,求m/(m+n)+m/(m-n)-n平方/(m平方-n平方)
m/(m+n)+m/(m-n)-n²/((m²-n²)
=(m²-mn+m²+mn-n²)/(m²-n²)
=(2m²-n²)/(m²-n²) [分子分母同时除以n²]
=[2(m/n)²-1]/[(m/n)²-1]
=1+(m/n)²/[(m/n)²-1]
=1+(5/3)²/[(5/3)²-1]
=1+16/25
=41/16
m=5n/3
原式=(m²-mn+m²+mn-n²)/(m²-n²)
=(2m²-n²)/(m²-n²)
=(2×25n²/9-n²)/(25n²/9-n²)
=(41n²/9)/(16n²/9)=41/16