Răspuns :
(1)... un tetraedru regulat , are toate muchiile congruente .
⇒ a) 6 muchi × 2cm = 12cm ;
b) A(totala)=6×2²×√3/4 =6√3cm²
(1)... un tetraedru regulat , are toate muchiile congruente .
⇒ a) 6 muchi × 2cm = 12cm ;
b) A(totala)=6×2²×√3/4 =6√3cm²