5的根號(hào)x³y-y根號(hào)4xy-6根號(hào)xy+x根號(hào)y/x-根號(hào)x/y
=5x√xy-2√xy-6√xy+√xy-1/y·√xy
=(5x-2-6+1-1/y)√xy
=(5x-7-1/y)√xy
=(5xy-7y-1)/y·√xy那我再問你一道吧 若根號(hào)17的整數(shù)部分是x 小數(shù)部分是y 求 x²+1/y的值∵根號(hào)17的整數(shù)部分是x 小數(shù)部分是y
∴x=4 y=√17-4
∴x²+1/y=16+1/(√17-4)
=16+√17+4
=20+√17