(√х+1/√х-1 - √х-1/√х+1 + 4√х) (√х-1/√х)

Question

(√х+1/√х-1 - √х-1/√х+1 + 4√х) (√х-1/√х)

Answer 1

(((sqrt(x)+1)^2-(sqrt(x)-1)^2)/(x-1)+4sqrt(x))*(sqrt(x)-1)/sqrt(x))=
=4sqrt(x)(1/(x-1)+1)(sqrt(x)-1)/sqrt(x))=
=4x/(sqrt(x)+1)