(1/n)²+5/n-2=0则2n²-5n-1=02m²-5m-1=0所以m和n是方程的2x²-5x-1=0根m+n=5/2,mn=-1/2则m²+n²=(m+n)²-2mn=29/4所以m/n=n/m=(m²+n²)/mn=-29/2