tlg di kerjain beserta caranya y bsk udah di kumpulin

Semoga membantu, maaf yg nomor dua ga ada jwbannya, Tapi kurang lebih Kaya gitu :)

Bentuk Akar dan Persamaan Eksponen.

Nomor 11.
[tex]\displaystyle \frac{3}{2-\sqrt{3}}\\ =\frac{3}{2-\sqrt{3}}~\frac{2+\sqrt{3}}{2+\sqrt{3}}\\ =6+3\sqrt{3}[/tex]

Nomor 12.
[tex]\displaystyle \frac{\sqrt{2}}{\sqrt{5}+\sqrt{3}}\\ \frac{\sqrt{2}}{\sqrt{5}+\sqrt{3}}~\frac{\sqrt{5}-\sqrt{3}}{\sqrt{5}-\sqrt{3}}\\ =\frac{\sqrt{10}-\sqrt{6}}{2}[/tex]

Nomor 13.
[tex]\displaystyle 1-\frac{1}{1+\sqrt{3}}+\frac{1}{1-\sqrt{3}}\\ =\frac{\sqrt{3}}{1+\sqrt{3}}+\frac{1}{1-\sqrt{3}}\\ =\frac{\sqrt{3}(1-\sqrt{3})+1(1+\sqrt{3})}{1-3}\\ =1-\sqrt{3}[/tex]

Nomor 14.
[tex]\displaystyle 3^{2x-3}=\frac{1}{3}\sqrt{27}\\ 3^{2x-3}=3^{-1}~3^{3/2}\\ 2x-3=\frac{1}{2}\\ x=\frac{7}{4}[/tex]

Nomor 15.
[tex]\displaystyle \boxed{\sqrt{a+b-2\sqrt{ab}}=\sqrt{a}-\sqrt{b}~\textrm{dengan}~a\ \textgreater \ b}\\ \sqrt{21-4\sqrt{5}}\\ =\sqrt{21-2\sqrt{20}}\\ =\sqrt{20+1-2\sqrt{20(1)}}\\ =\sqrt{20}-\sqrt{1}\\ =2\sqrt{5}-1[/tex]