Question

What is the slope of the polar curve r=cos(2 theta) at theta =0 and theta=pi/2. (This is Calculus II)

Answer 1

dr/d,theta

Answer 2

it may be simpler in this case to just convert it to xy coords

Answer 3

parametric xy coords that is

Answer 4

cos(2t) = cos^2(t) - sin^2(t)
= 2cos^2(t) - 1

x = r cos(t); y=sin(t); r^2 = x^2 + y^2


those might play into a parametric solution