a.6 căn 12 – 5 căn 27+2 căn 48 b.căn(1-2 căn 3 mủ 2) – căn 4+2 căn 3 28/09/2021 Bởi Melanie a.6 căn 12 – 5 căn 27+2 căn 48 b.căn(1-2 căn 3 mủ 2) – căn 4+2 căn 3
a, `6\sqrt{12}-5\sqrt{27}+2\sqrt{48}` `=6\sqrt{4.3}-5\sqrt{9.3}+2\sqrt{16.3}` `=6.2\sqrt{3}-5.3\sqrt{3}+2.4\sqrt{3}` `=12\sqrt3-15\sqrt3+8\sqrt3` `=\sqrt3(12-15+8)` `=5\sqrt3` b, `\sqrt{(1-2\sqrt3)^2}-\sqrt{4+2\sqrt3}` `=|1-2\sqrt3|-\sqrt{1+2\sqrt3+3}` `=2\sqrt3-1-\sqrt{(1+\sqrt3)^2}` `=2\sqrt3-1-1-\sqrt3` `=\sqrt3-2` Bình luận
a,
`6\sqrt{12}-5\sqrt{27}+2\sqrt{48}`
`=6\sqrt{4.3}-5\sqrt{9.3}+2\sqrt{16.3}`
`=6.2\sqrt{3}-5.3\sqrt{3}+2.4\sqrt{3}`
`=12\sqrt3-15\sqrt3+8\sqrt3`
`=\sqrt3(12-15+8)`
`=5\sqrt3`
b,
`\sqrt{(1-2\sqrt3)^2}-\sqrt{4+2\sqrt3}`
`=|1-2\sqrt3|-\sqrt{1+2\sqrt3+3}`
`=2\sqrt3-1-\sqrt{(1+\sqrt3)^2}`
`=2\sqrt3-1-1-\sqrt3`
`=\sqrt3-2`