((x+1)^{\frac{1}{2}}+(x-1)^{\frac{1}{2}})^2=
źródło:
stosujemy wzór
(a+b)^2=a^2+2ab+b^2
…
=[(x+1)^{\frac{1}{2}}]^2+2*\sqrt{x+1}*\sqrt{x-1}+[(x-1)^{\frac{1}{2}}]^2=
=x+1+2\sqrt{(x+1)(x-1)}+x-1=
=2x+2\sqrt{x^2-1}