a-b分之a+b+2√ab-【（a+根号ab分之根号a）-（b-根号ab分之根号b）】÷(b+根号ab分之根号a)
=(a+b+2√ab)/(a-b)-【1/(√a+√b)+1/(√a-√b)】×(b+√ab)/√a
=(a+b+2√ab)/(a-b)-【2√a/(a-b)】×(b+√ab)/√a
=(a+b+2√ab)/(a-b)-(2b+2√ab)/(a-b)
=(a-b)/(a-b)
=1