Question

Precalc: Find the foci and vertices of the ellipse with equation: x^2/4+y^2/16=1

Answer 1

ok from general ellipse equation we know that
center is (0,0)
a^2 = 16 --> a = 4
b^2 = 4 --> b = 2

Find Foci
a^2 = b^2 +c^2
16 = 4 + c^2
c^2 = 12
c = 2sqrt(3)

Vertices: (0,-4) and (0,4)
Foci: (0,-2sqrt3) and (0,2sqrt3)