5x²y+（m-5）x³y²-（n-3/2）x²y³+5xy五次方则m=n=减了后不含五次项！

5x²y+（m-5）x³y²-（n-3/2）x²y³+5xy五次方则m=n=减了后不含五次项！
5x²y+（m-5）x³y²-（n-3/2）x²y³+5xy五次方
则m=
n=
减了后不含五次项！

5x²y+（m-5）x³y²-（n-3/2）x²y³+5xy五次方则m=n=减了后不含五次项！
五次方指的是哪个的五次方啊?