daca AB - diametru = 2R=24 cm⇒ Δ ABC - dreptunghic in C ; AB- ipotenuza
daca m(BC)=60°⇒ ∡ BAC = 60:2=30°⇒ ∡ ABC= 60°
⇒T∡30°⇒ BC = AB/2 = 24/2=12 cm
ΔABC dr⇒ TP⇒ AB² = AC²+BC²⇒ 576 = 144+AC²⇒
⇒AC² = 576-144=432⇒ AC= 12√3cm
PΔABC = 12+24+12√3 = 36+12√3 cm