Question

How would you switch the polar coordinates into the rectangular coordinates of each point.

(5,(pi/4))
(-2,(pi/6))

Answer 1

http://www.teacherschoice.com.au/maths_library/coordinates/polar_-_rectangular_conversion.htm

Answer 2

Remember that x=rcos(theta) and y=rsin(theta)

Answer 3

Thank you! That website looks like a great help!

Answer 4

R is 5 and theta is pi/4 for 1st coordinate points

And R is -2 and theta is pi/6 for the 2nd coordinate points

Answer 5

you're welcome

Answer 6

Yes but I converted the coordinates so they are degrees so it is easier! Like for the first one the (pi/4)=45 degrees

Answer 7

Yeah convert radians to degrees and then plug in values of r and theta to the 2 formulas

Answer 8

With the equation from the website it becomes
(5 cos 45, 5 sin 45)

Answer 9

So the coordinates for that first one would become (2.63,4.25)

Answer 10

Yeah now put those coordinate points into rectangular form

Answer 11

I just did

Answer 12

I got (4.999, .069)

Answer 13

How did you get (2.63, 4.25)?

Answer 14

I times the numbers together

Answer 15

Ohh I apologize calculator in wrong mode

Answer 16

So I was right? Because I checked on wolfram and for 5 cos 45 it is getting 3.555.......

Answer 17

http://www3.wolframalpha.com/Calculate/MSP/MSP53441gdb9hgi594gbaha00006452ce0i8gbcahe5?MSPStoreType=image/gif&s=42&w=443.&h=20.

Answer 18

Yeah my calculator was in radians that is how I got the 2.64 but it should be in degrees and I got 3.53 so yeah wolfram is right

Answer 19

So my calculator should be in degrees when multiplying these?

Answer 20

And you should get the same for 5sin(45)

Answer 21

Yeah because theta is in terms of degrees not radians

Answer 22

Alright, Thank you again!

Answer 23

Yup anytime. You can also leave theta in radians and have 5cos(pi/4) and you get the same answer

Answer 24

Alright cool!! (:

Answer 25

Just remember to check if theta is in radians or degrees and put your calculator into the respective mode

Answer 26

I just did and have gotten the correct answer

Answer 27

Yeahh!! The conversion between coordinates is fairly easy to understand and do. Just try and memorize them

Answer 28

When I did the 5 sin 45 it gives me the same answer as the first one with cos

Answer 29

Yup it's correct From the unit circle you can see that at 45 degrees cos and sin are the same

Answer 30

Alright, that scared me for a moment. Than kyou

Answer 31

Having the unit circle is handy

Answer 32

Haha it's okay to check make sure you have it down

Answer 33

I printed one off