Răspuns:
1.a) 2,(3) = (23-2)/9 = 21/9 = 7/3
b) (7+11)/2 = 18/2 =9
2. a) 4/rad.2 = 4rad.2/ (rad.2 × rad.2) = 4 rad.2 / 2 =
. =2rad.2
b) 3rad5 □ 2rad.11
<=> rad(3²×5) □ rad(2²×11)
<=> rad45 □ rad 44
<=> 45 > 44 ==> 3rad5 > 2rad11
3. l = 3/4×L = 3×12/4 = 9cm
a) P = 12 ×2 + 9× 2 = 24+18 = 42cm
b) A = L×l = 12×9 = 108cm
