Đáp án+Giải thích các bước giải:
10)
`2sqrt5 - sqrt125 - sqrt80 + sqrt605`
`= 2sqrt - 5sqrt5 - 4sqrt5 +11sqrt5`
`= (2-5-4+11)sqrt5`
`= 4sqrt5`
11)
`sqrt49 - 5sqrt28 + 1/2* sqrt63`
`= 7 - 10sqrt7 + (3sqrt7)/2`
`= 7 - (17sqrt7)/2`
12)
`3/4sqrt50 - 2/3sqrt18 + 3/2sqrt32`
`= (15sqrt2)/4 - 2 sqrt2 + 6sqrt2`
`= (15sqrt2)/4 - (8sqrt2)/4 + (24sqrt2)/4`
`= (31sqrt2)/4`
13)
`(2sqrt5 + 3sqrt20) * sqrt5`
`= (2sqrt5 + 6sqrt5)* sqrt5`
`= 8sqrt5 * sqrt5`
`= 8*5`
`= 40`
14)
`2sqrt3(sqrt27 + 2sqrt48- sqrt75)`
`= 2sqrt3(3sqrt3 + 8sqrt3 - 5sqrt3)`
`= 2sqrt3 * 6sqrt3`
`= 2*3*6`
`= 36`
15)
`(2sqrt6 - 4sqrt3 - 1/4sqrt8)3sqrt6`
`= (2sqrt6 - 4sqrt3 - sqrt2/2) 3sqrt6`
`= 36 - 12sqrt18 - (3sqrt12)/2`
`= 36 - 36sqrt2 - (6sqrt3)/2`
`= 36 - 36sqrt2 - 3sqrt3`
