Question

O prisma triunghiulara regulata are toate muchiile de lungime 4 cm . Volumul prismei este de ... cm .

Answer 1

    
$\text{Prisma triunghiulara regulata are toate muchiile egale} \\ \text{se numeste \underline{tetraedru regulat}.}\\ \\ Notatii: \\ a = 4\;cm = muchia \;tetraedrului. \\ V=volumul \;tetraedrului. \\ \\ Rezolvare: \\ \\ V= \frac{a^3\cdot \sqrt{2} }{12}= \frac{4^3\cdot \sqrt{2} }{12}= \frac{64\sqrt{2} }{12}=\boxed{\frac{16\sqrt{2} }{3}\;cm^3}$

Answer 2

V=Aria bazei*h
A=l*lrad3/4
A=4*4rad3/4
A=4rad3cm patrati

V=4rad 3 cm patrati*4cm
V=16rad3 cm cubi

rad=Radica
/=supra
l*l=latura la a doua