Question

Thanks for helping! Help with symmetries!

Identify, graph, and state the symmetries of each polar equation. Write the scale that you are using for the polar axis.

r=9cos(5 theta)

Answer 1

@Hero @jim_thompson5910 @phi @zepdrix @SithsAndGiggles @wio @sleepyjess @Data_LG2

Answer 2

cosine is the only even function ( a mirrored symmetry) while tangent and sine are odd functions (symmetry at the origin)

Answer 3

It asks me for symmetry about the polar axis, etc.

Answer 4

first we need to graph this... you may need to let theta = pi/2, pi , 3pi/2 , 2pi , pi/4, pi/3, pi/6 to figure out your r

and graph it (r, theta)

Answer 5

http://assets.openstudy.com/updates/attachments/557cd647e4b05cad71f0df73-lyralei-1434246339610-capture.png

Answer 6

Like this?

Answer 7

umm let me check in a bit. I am with someone atm

Answer 8

ok cool

Answer 9

is that desmos?

Answer 10

yea

Answer 11

cool. so we have a flower in the graph

Answer 12

yup

Answer 13

I know for a fact it has symmetry about the polar axis

Answer 14

but I need help with the rest

Answer 15

yeah.. I see a petal on the far right oh wow my draw is broken

Answer 16

that one shows symmetry on that one petal only

Answer 17

yup

Answer 18

But there was an equation thing for it that I used and it worked.

Answer 19

equation thing?

Answer 20

since cos is always equal

Answer 21

r=9cos(5(-theta))=

Answer 22

9cos(-5 theta)

Answer 23

9cos(5 theta)

Answer 24

and it's also the only even function...

Answer 25

yup