c)
`\sqrt{8-2\sqrt{15}}+\sqrt{5}+\sqrt{3}`
`=\sqrt{5-2\sqrt{3}\sqrt{5}+3}+\sqrt{5}+\sqrt{3}`
`=\sqrt{(\sqrt{5}-\sqrt{3})^2}+\sqrt{5}+\sqrt{3}`
`=|\sqrt{5}-\sqrt{3}|+\sqrt{5}+\sqrt{3}`
`=\sqrt{5}-\sqrt{3}+\sqrt{5}+\sqrt{3}`
`=2\sqrt{5}`
d)
`(x+2\sqrt{x}-3)/(\sqrt{x}-1)`
`=(x-\sqrt{x}+3\sqrt{x}-3)/(\sqrt{x}-1)`
`=[\sqrt{x}(\sqrt{x}-1)+3(\sqrt{x}-1)]/(\sqrt{x}-1)`
`=[(\sqrt{x}+3)(\sqrt{x}-1)]/(\sqrt{x}-1)`
`=\sqrt{x}+3`
