Question

calculați:
(√5+2) la a doua+(√5-2) la a doua.

Answer 1

(a±b)²=a²±2•a•b+b²
Bafta! :))

Answer 2

(rad5 +2)^2=> 5+2*2*rad5 +4 => 5+4*rad 5 +4=> 9 +4*rad5 (rad5 -2)^2=> 5-2*2*rad5 +4 => 5-4*rad 5 +4 => 9 -4*rad5