5x^(3n+5)y^(3m-1)÷[-5x^(n+1)y^m]^2=1/5x^(2)y^25x^(3n+5)y^(3m-1)÷25x^(2n+2)y^2m=1/5x^(2)y^21/5x^(3n+5-2n-2)y^(3m-1-2m)=1/5x^(2)y^21/5x^(n+3)y^(m-1)=1/5x^(2)y^2那么n+3=2,m-1=2,所以n=-1,m=3将此代入上式...