`(\sqrt{12}-2\sqrt{18})·\sqrt{2/2}`

`=(\sqrt{12}-2\sqrt{18})·1`

`=\sqrt{12}-2\sqrt{18}`

`=2\sqrt{3}-6\sqrt{2}`

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`(\sqrt{12}-2\sqrt{18})·\sqrt{2}/2`

`=((\sqrt{12}-2\sqrt{18})·\sqrt{2})/2`

`=(2\sqrt{3}·\sqrt{2}-2\sqrt{18}·\sqrt{2})/2`

`=(2\sqrt{6}-12)/2`

`=\sqrt{6}-6`