化简求值2根号a-【a-根号a】分之a+根号a【a等于2】
问题描述:
化简求值2根号a-【a-根号a】分之a+根号a【a等于2】
答
原式=2√a - (a +√a)/(a-√a)=2√a - √a(√a +1)/[ √a (√a -1) ]=2√a - (√a +1)/(√a -1) 分母有理化=2√a - (√a +1)²/[ (√a +1)(√a -1) ]=2√a - (a+2√a +1)/(a-1) 通分=2√a (a-1)/(a-1) -(a+2√a ...