3-根号5/根号5-1怎么化解成 根号5-1/2

问题描述:

3-根号5/根号5-1怎么化解成 根号5-1/2

(3 -√5) / (√5 -1) = [(3 - √5) * (√5+1)] / [(√5 - 1) * (√5 +1)] = [3√5 +3 - 5 - √5) / [(√5)^2 - 1^2] = (2√5 - 2) / (5 - 1) = (2√5 - 2) / 4 = (√5 - 1) / 2