Posted by Tati on .
Convert from polar to rectangular r=3cos2theta

precalculus 
bobpursley,
x= r cosTheta=3cos(2Theta)cosTheta
y= r sin Theta=3cos(2Theta)sinTheta 
precalculus 
Bosnian,
In google type :
r=3cos2theta
When you see list of results click on :
Advanced Math: precal, trig identities, conversion
You will see answer. 
precalculus 
Tati,
Identities r everywhere!!! :/, thank you 4 the info appreciated