`(\sqrt{3}+\sqrt{2})²`
`=(\sqrt{3})² +2.\sqrt{3}.\sqrt{2}+(\sqrt{2})²`
`=3+2.\sqrt{6}+2`
`=5+2\sqrt{6}`
`-----`
`(\sqrt{5}-\sqrt{3})²`
`=(\sqrt{5})²-2.\sqrt{5}.\sqrt{3}+(\sqrt{3})²`
`=5-2.\sqrt{15}+3`
`=8-2\sqrt{15}`
`-----`
`(2-\sqrt{3})(2+\sqrt{3})`
`=2²-(\sqrt{3})²`
`=4-3=1`
