Polar equations  Help?
posted by Tabby .
i need to graph the polar equation
2 = r cos (theta + 180) on one of the graphs that looks like a flattened globe.
So far I have
2=r cos180 costheta + r sin180 sintheta
what do i do now?

Isn't cos(Theta+180)= cosTheta ?
checking the hard way...
cos(A+B)=cosAcosBsinAsinB
cos(Theta+180)= cosThetacos180sinThetasin180= cosTheta.
2= rcosTheta
r= 2/cosTheta.
Graph it. 
thank you so much, I don't know how i missed that identity.
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