Question

Eliminate the parameter. x = 3 cos t, y = 3 sin t

Answer 1

Use this trig identity:
\[\cos^2 x + \sin^2 x = 1\]

Answer 2

i dont remember how.....

Answer 3

x = 3 cos t; x^2 = 9 cos^2
Do the same for the 'y' side.
Then, apply the identity.

Answer 4

y=3 sin t;y^2=9 sin ^2
9cos^2+9sin^2=1??

Answer 5

Nopeee. x^2 + y^2 = 9 cos^2 t + 9 sin^2 = ?
9(cos^2 t + sin^2 t) = 9(1) = 9
x^2 + y^2 = ... = 9

Answer 6

whats the ...in between the =

Answer 7

The 9 cos^2 t + 9 sin^t.
I factored out the 9. Then I can apply the trig identity.
This parametric equation is for a circle of radius 3.

Answer 8

sin^2 t*

Answer 9

thank you so much.