68. Parametric Circles and Ellipses Set your grapher to parametric and radian mode and your window as follows:
Tmin =0, Tmax =7, Tstep =0.1Xmin=−4.7,Xmax=4.7,Xscl=1Ymin=−3.1,Ymax=3.1,Yscl=1
(a) Graph the parametric equations x=cost and y=sint. You should get a circle of radius 1 .
(b) Use a transformation of the parametric function of x to produce the graph of an ellipse that is 4 units wide and 2 units tall.
(c) Use a transformation of both parametric functions to produce a circle of radius 3 .
(d) Use a transformation of both functions to produce an ellipse that is 8 units wide and 4 units tall.
(You will learn more about ellipses in Chapter 8.)