Đáp án+Giải thích các bước giải:

`a)`

`(\sqrt{2}+1)/\sqrt{2}`

 `=(\sqrt{2}(\sqrt{2}+1))/(\sqrt{2}*\sqrt{2})`

`=(\sqrt{2}^2+\sqrt{2})/2`

`=(2+\sqrt{2})/2`

`=1+\sqrt{2}/2`

`b)`

`13/(3-\sqrt{2})`

`=(13(3+\sqrt{2}))/((3-\sqrt{2})(3+\sqrt{2}))`

`=(39+13\sqrt{2})/(3^2-\sqrt{2}^2)`

`=(39+13\sqrt{2})/(9-2)`

`=(39+13\sqrt{2})/7`

`c)`

`(\sqrt{3}-\sqrt{2})/\sqrt{6}`

`=(\sqrt{6}(\sqrt{3}-\sqrt{2}))/\sqrt{6}^2`

`=(\sqrt{18}-\sqrt{12})/6`

`=(3\sqrt{2}-2\sqrt{3})/6`