化简:a+1/(根号a-1)平方-4a+4根号a/(a-1)平方

问题描述:

化简:a+1/(根号a-1)平方-4a+4根号a/(a-1)平方
重新补充题目
根号a+1/(根号a-1)平方-4a+4根号a/(a-1)平方

t=根号a
t+1/(t-1)^2 - 4t^2+4t /(t^2-1)^2
t+1/(t-1)^2 - 4t^2+4t/(t+1) ^2(t-1)^2
(t+1)^3/(t+1) ^2(t-1)^2 - 4t^2+4t/(t+1) ^2(t-1)^2
(t+1)^3-4t^2-4t/(t+1) ^2(t-1)^2
t^3-t^2-t+1/(t+1) ^2(t-1)^2
(t-1)(t^2-1)/(t+1) ^2(t-1)^2
1/t+1
1/根号a+1
答案:根号a-1/a-1 一样的问题啊~