根号8+根号18
=2√2+3√2
=5√2
2根号12+根号48
=4√3+4√3
=8√3
3根号20-根号45-根号5分之1
=4√5-3√5-√5/5
=4√5/5
根号9分之2+根号50-根号32
=√2/3+5√2-4√2
=4√2/3还差一个啊6-根号2分之3-根号3分之26-根号2分之3-根号3分之2=6-√6/2-√6/3=6-5√6/6