`2/(\sqrt{2} - 1) + (\sqrt{2} - \sqrt{6})/(\sqrt{3} - 1)`
`= 2/(\sqrt{2} - 1) - (\sqrt{6} - \sqrt{2})/(\sqrt{3} - 1)`
`= 2/(\sqrt{2} - 1) - (\sqrt{2}(\sqrt{3} - 1))/(\sqrt{3} - 1)`
`= 2/(\sqrt{2} - 1) - \sqrt{2}`
`= 2/(\sqrt{2} - 1) - (\sqrt{2}(\sqrt{2} - 1))/(\sqrt{2} - 1)`
`= (2 - 2 + \sqrt{2})/(\sqrt{2} - 1)`
`= \sqrt{2}/(\sqrt{2} - 1)`
`= (\sqrt{2}(\sqrt{2} + 1))/((\sqrt{2} - 1)(\sqrt{2} + 1))`
`= 2 + \sqrt{2}`
