Đáp án+Giải thích các bước giải:
`a)`
`3\sqrt8-2\sqrt50+10\sqrt72`
`=3\sqrt{4.2}-2\sqrt{25.2}+10\sqrt{36.2}`
`=3.2\sqrt2-2.5\sqrt2+10.6\sqrt2`
`=6\sqrt2-10\sqrt2+60\sqrt2`
`=56\sqrt2`
`b)`
`3\sqrt75-\sqrt147+\sqrt{4/3}`
`=3\sqrt{25.3}-\sqrt{49.3}+\sqrt4/\sqrt3`
`=3.5\sqrt3-7\sqrt3+2/\sqrt3`
`=15\sqrt3-7\sqrt3+(2\sqrt3)/3`
`=8\sqrt3+(2\sqrt3)/3`
`=(24\sqrt3+2\sqrt3)/3`
`=(26\sqrt3)/3`
`c)`
`(\sqrt3+\sqrt2)^2-2\sqrt6`
`=(\sqrt3)^2+2.\sqrt3.\sqrt2+(\sqrt2)^2-2\sqrt6`
`=3+2\sqrt6+2-2\sqrt6`
`=3+2`
`=5`
`d)`
`\sqrt{(2-\sqrt3)^2}+\sqrt{(1-\sqrt3)^2}`
`=|2-\sqrt3|+|1-\sqrt3|`
`=2-\sqrt3+\sqrt3-1` (Vì `2>\sqrt3;\sqrt3>1`)
`=2-1`
`=1`
`e)`
`(2+\sqrt3).\sqrt{7-4\sqrt3}`
`=(2+\sqrt3).\sqrt{4-4\sqrt3+3}`
`=(2+\sqrt3).\sqrt{2^2-2.2.\sqrt3+(\sqrt3)^2}`
`=(2+\sqrt3).\sqrt{(2-\sqrt3)^2}`
`=(2+\sqrt3).|2-\sqrt3|`
`=(2+\sqrt3)(2-\sqrt3)`
`=2^2-(\sqrt3)^2`
`=4-3`
`=1`
