Hello-- I have four equations I simply can't figure out:

r=cot(theta)csc(theta)

r=8sin(theta)

r=2cos(theta)sin(theta)

rsin(theta+pi/6)=2

I tried squaring each of these in hopes of finding something to work with, but I'm lost...please help!!

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- September 26th 2007, 03:47 PMriverjibConverting polar equations to parametric
Hello-- I have four equations I simply can't figure out:

r=cot(theta)csc(theta)

r=8sin(theta)

r=2cos(theta)sin(theta)

rsin(theta+pi/6)=2

I tried squaring each of these in hopes of finding something to work with, but I'm lost...please help!! - September 26th 2007, 04:35 PMSoroban
Hello, riverjib!

Do you mean "polar to rectangular"?

We need the conversion formulas:

.

Quote:

Multiply by

Substitute: .

Then: .

Square both sides: .

Quote:

Substitute: .

Quote:

Multiply by

Substitute: .

Square both sides: .

Quote:

Multiply by 2: .

Substitute: .

- September 26th 2007, 04:48 PMriverjibThank you so much!
Thank you! I did 40 problems like this successfully, and got stumped on these four almost two hours ago. I actually figured out just before you posted that I could multiply one side by r as long as I did the same to the other side (big duh! on my part), and that solved the problem of the missing r's. But I was still stuck on the fourth equation, and you helped me just as I was beginning to lose my mind.