Calculus
posted by Sarah .
I'm extremely confused on what to do in part a of this question.
Consider the curve given by x=3sin(theta), y=1+2cos(theta), 0<=theta<=3pi/2
(a) Eliminate the parameter and find a Cartesian (Rectangular) equation for the curve.

Your basic replacement identities are:
r^2 = x^2 + y^2
x = rcosØ and y = rsinØ or cosØ = x/r and sinØ = y/r
so you have:
x =3sinØ > sinØ = x/3
y = 1+2cosØ
cosØ = (y1)/2
but we know sin^2 Ø + cos^2 Ø = 1
x^2/9 + (y1)^2 /4 = 1
looks like an ellipse to me
Respond to this Question
Similar Questions

precalc
Eliminate the parameter and write the corresponding rectangular equation. X=2cos theta, y=4sin theta 
Calculus
I wanted to confirm that I solved these problems correctly (we had to convert the polar curves to Cartesian equations). 1.rcos(theta)=1 x=1 2.r=2*sin(theta)+2*cos(theta) r^2=2rsin(theta)+2rcos(theta) x^2+y^2=2y+2x (a little unsure … 
Advanced Math
Identify the polar form of the linear equation 4x+3y=10. x=rcos(theta),y=rsin(theta) 4x+3y=4rcos(theta)+3rsin(theta)=10 r=10/(4cos(theta)+3sin(theta) I got it wrong 
Precalculus(NEED HELP ASAP PLEASE!!)
cot(theta)= 3 pi < theta < 3pi/2 Find: sin(theta)= 1 ? 
calculus
Eliminate the parameter and write the corresponding rectangular equation whose graph represents the curve. x=4+2cos(theta) y=1+2sin(theta) 
Calculus
Use the given equation to answer the following questions. (Enter your answers from smallest to largest.) r = 8cos(¦È) 0 ¡Ü ¦È < ¦Ð (a) Find the points on the given curve where the tangent line is horizontal. theta= theta= … 
Calculus
Convert the curve to an equation in rectangular coordinates: x=sin theta + 1 y=2cos theta  1 
Math Please Help
Eliminate the parameter and sketch the curve. x=cos(theta) , y=cos^2(theta) + 8cos(theta) 
Calculus Question! ASAP!
Hello! I have this problem: x(dx)/sqrt(9x^2) I was wondering why I can't use trig substitution and substitute sqrt(9x^2) for sqrt(1sec^2) and having: integral x = 3sin(theta) dx = 3cos(theta)d(theata) integral 3sin(theta)(3cos(theta))/3cos(theta) … 
Algebra 2
What values for theta(0 <= theta <= 2pi) satisfy the equation?