[tex]\it radical\ \ din\ \ 4\ \ se\ \ scrie\ \ \sqrt4\\ \\ \sqrt4=4^{\frac{1}{2}}\\ \\ Expresia\ devine:\\ \\ 4+4^{\frac{1}{2}}\\ \\ Dar,\ \ 4^{\frac{1}{2}}\cdot4^{\frac{1}{2}}=4^{\frac{1}{2}+\frac{1}{2}} =4^{\frac{1+1}{2}}=4^\frac{2}{2}=4^1=4\\ \\ Acum,\ \ expresia\ \ devine:\\ \\ 4^{\frac{1}{2}}\cdot4^{\frac{1}{2}}+4^{\frac{1}{2}}=4^{\frac{1}{2}}(4^{\frac{1}{2}}+1)[/tex]
