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Question
How do I convert 9 cis 300 degrees to rectangular coordinates? I need to find an exact answer. Thanks very much for your help!
Hi Keli,
The polar coordinates r and θ can be converted to cartesian coordinates x and y by using the trigonometric substitutions
x = r.cosθ
y = r.sinθ
For r = 9 and θ = 300
x = 9.cos 300
= 9.cos (360 - 300)
= 9.cos 60
= 9.(0.5)
= 4.5
y = 9.sin 300
= 9.-{sin (360 - 300)}
= 9.(-sin 60)
= 9.-(sqrt3)/2
= -4.5(sqrt3)
= -4.5(1.732)
= -7.794
In the opposite direction,
r^2 = x^2 + y^2
θ = arctan (y/x) (basically)
Regards.
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| Rating(1-10) | Knowledgeability = 10 | Clarity of Response = 10 | Politeness = 10 |
| Comment | Thank you very much for your outstanding help! Thanks also for showing me the steps so that hopefully, I may do it on my own next time! I really appreciate it! | ||
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Ahmed Salami
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I can provide good answers to questions dealing in almost all of mathematics especially from A`Level downwards. I believe i would be very helpful in calculus and can as well help a good deal in Physics with most emphasis directed towards mechanics.
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An engineering graduate. I have been doing maths and physics all my life.
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