# Math Help - More Parametric

1. ## More Parametric

Use the parametric equations of the ellipse x=5cos(theta), y=7sin(theta) to find the area enclosed by the ellipse for
(-5*radical 3)/2, less than or equal to x, less than or equal to (5*radical 3)/2

Find the length of the curve:

x=e^(2t)*cos(2t)
y=e^(2t)*sin(2t)
0 less than or equal to t less than or equal to Pi/2

Again, I got answers but I'm not sure if they're right. I think they're wrong.

2. Originally Posted by thegame189
Use the parametric equations of the ellipse x=5cos(theta), y=7sin(theta) to find the area enclosed by the ellipse for
(-5*radical 3)/2, less than or equal to x, less than or equal to (5*radical 3)/2

Find the length of the curve:

x=e^(2t)*cos(2t)
y=e^(2t)*sin(2t)
0 less than or equal to t less than or equal to Pi/2

Again, I got answers but I'm not sure if they're right. I think they're wrong.
It would help in troubleshooting your difficulties if you showed your working.

3. For the first one, I got that I needed to integrate from -pi/6 to pi/6 with the integral 7sin(theta)5sin(theta).

I have to multiply by two to get both sides of the ellipses, so it's 70*integral of sin^2 (theta). I then turned that into 35*the integral 1 - cos(2theta). I integrated that into 35*(theta - (1/2)sin(2theta) and then plugged in the -pi/6 and pi/6.

What I got wasn't correct according to the homework answer.