Question

Can someone tell me what the graph of r=cos (5/2 x angle) should look like?

Answer 1

I found this nice applet to graph polar functions

http://www.ies.co.jp/math/java/calc/sg_kyok/sg_kyok.html

I set r(t) = cos(5*t/2)
and set the range form -6.28 to 6.28 (appr. -2π to 2π)
and the zoomed in a bit