Question

Answer 1

Xét tử:

`2 sqrt (3 + sqrt (5 - sqrt ( sqrt 12 + 1)^2))`

`= 2 sqrt (3 + sqrt ( 5 - sqrt 12 - 1))`

`= 2 sqrt (3 + sqrt (3  + 2.sqrt4 + 1))`

`= 2 sqrt (3 + sqrt (sqrt 3 + 1)^2)`

`= 2 sqrt (3 + sqrt 3 + 1)`

`= 2 sqrt (4 + sqrt 3)`.

Xét mẫu `= sqrt 2(sqrt 3 + 1)`

`=> (2 sqrt (4 + sqrt 3))/(sqrt 2(sqrt 3+1))`

`= (sqrt 8 + sqrt 6)/(sqrt 3 + sqrt 1)`

Answer 2

Xét tử:

2√3+√5−√√12+1223+5-12+12

=2√3+√5−√12−1=23+5-12-1

=2√3+√3 +2.√4+1=23+3 +2.4+1

=2√3+√√3+12