Question

Ex 3 și 4 va rog dau cororana!!!

Answer 1

[tex]3)a^2=(\sqrt{4-\sqrt{15}}+\sqrt{4+\sqrt{15}})^2=\\ \\ =4-\sqrt {15}+2\sqrt{(4-\sqrt{15})\times (4+\sqrt{15}}+4+\sqrt{15}=\\ \\ =8+2\sqrt{16-15}=8+2\sqrt 1=8+2=10.[/tex]



$\displaystyle 4)\frac{x\times y}{z}=\frac{(p^2+p)\times(p-1)}{p^2-1}=\frac{p\times(p+1)\times(p-1)}{(p-1)\times (p+1)}=p$