Question

identify the graph of the parametric equation: x=sint and y=2cost

Answer 1

x^2=sin^2(t)
y^2/4=cos^2(t)
x^2+y^2/4=sin^2+cos^2=1

this is an ellipse. Also we know x=sint,y=cost is a circle, and here we are just stretching along the y axis by a factor of two making an ellipse

Answer 2

ok. is it possible to graph this on a calculator?

Answer 3

you can graph it using two functions. one for the top and one for the bottom. solve for y:

y^2=4*(1-x^2)
y=+sqrt(4*(1-x^2))
y=-sqrt(4*(1-x^2))

on a calculator you need to make two seperate function for the top and bottom half and plot both.

Answer 4

ok thanks

Answer 5

yw