## anonymous 3 years ago How to convert polar to cartesian and cartesian to polar.

1. anonymous

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2. anonymous

for polar to cartesian think about writing r in terms of x and y, and theta in terms of x and y

3. anonymous

I think what you wrote at the top is polar to cartesian. Because your finding x and y. I really need to know how to find cartesian to polar.

4. anonymous

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5. anonymous

I think so Im given something like that with this tan^-1

6. anonymous

i know what the answer is. I'm trying to help you get there yourself. Work out those two equations i drew for you.

7. anonymous

$\sqrt{x^2+y^2}=r$

8. anonymous

excellent!

9. anonymous

$x+y=r$

10. anonymous

no. not so good.|dw:1366123658835:dw|

11. anonymous

your first solution was correct

12. anonymous

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13. anonymous

oh sorry

14. anonymous

what about for theta?

15. anonymous

would it be $\frac{ \sqrt{x} }{ \sqrt{y} }$

16. anonymous

how did you get that?

17. anonymous

theta = tan^-1 (y/x)

18. anonymous

great. well done. that is it. you have finished.

19. anonymous

thank you

20. anonymous

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