Question

Help with polar Graph:
How and why is the range of this polar graph from -pi/4 to pi/4

r^2=36cos(2theta)

Answer 1

shouldn't that be cis(2theta) ?

Answer 2

cis, what trig function is that?

Answer 3

cis is special for polar

Answer 4

it means cos + i sin

Answer 5

no its just cos

Answer 6

cis(x) = cos(x) + isin(x)

Answer 7

ok

Answer 8

then that means that the polar graph only goes along the real axis

Answer 9

which is pretty useless considering it is a polar graph

Answer 10

yeah, the cos needs to be or have a max value from 0 to1

Answer 11

but that would be if the wuestion said domain. Not range

Answer 12

right, but then we need to determine what values would give us that domain

Answer 13

fine. That works.