# Math Help - Polar to rectangular form

1. ## Polar to rectangular form

r^2= sec^2(theta) - tan^2(theta)

2. $\sec(x)\ne\frac{1}{\sin(x)}$

3. Thank you!!!!!

4. Hello, cmr7!

Someone created this problem as a joke . . .

Write in rectangular form: . $r^2\:=\: \sec^2\!\theta - \tan^2\!\theta$

We're expected to know this identity: . $\sec^2\!A - \tan^2\!A \:=\:1$

. . and this conversion: . $r^2 \:=\:x^2+y^2$

So: . $r^2 \:=\:\sec^2\!\theta - \tan^2\!\theta\;\text{ becomes: }\:r^2 \:=\:1 \quad\Rightarrow\quad x^2+y^2 \:=\:1$

5. Originally Posted by Soroban
Hello, cmr7!

Someone created this problem as a joke . . .

Yeah, apparently for me.

6. ## me too

I am in the class right now so all this should be fresh on my mind and it got past me also. I am going on 4 night sin a row of studying for this final. Maybe I should just get some sleep now haha!