Question

Medals medals medals!
the polar coordinates of a point are given. Find the rectangular coordinates of each point...
1. (2, 3pi/4)
2. (-4, 7pi/6)
3. (2/3, -2pi/3)

Answer 1

@dan815 @Compassionate

Answer 2

\(\Large x= r\cos \theta \)
\(\Large y= r\sin \theta \)

Answer 3

so if you're trying first one

x= 2 cos (3pi/4) =...
y= 2 sin (3pi/4) = ..

Answer 4

okay, let me work this out (thanks!!) one sec

Answer 5

\[-\sqrt2, \sqrt2\] ?

Answer 6

\(\huge \checkmark \)

Answer 7

same formula for others

Answer 8

awesome! Thank you! okay
okay correct me if im wrong, the next one is \[-\sqrt3/2, 2\]

Answer 9

2 is correct...
are you sure
-sqrt 3/2 is correct??

Answer 10

no, i'll trying again but im stuck. Im not exactly the go to person on math so i move pretty slow

Answer 11

cos 7pi/6 is indeed -sqrt 3/2
but x is actually r cos theta = -4 * (-sqrt 3/2) = 2sqrt 3 :)

Answer 12

alright, thats clear! thanks

Answer 13

tell me what u get for the last one...

Answer 14

alright, brace yourself

Answer 15

*fingers crossed*

Answer 16

\[(-4/3, 4\sqrt3/3)\]

Answer 17

what did u take as 'r' ?

Answer 18

2/3?

Answer 19

and cos (-2pi/3) = -1/2

so x= (2/3)*(-1/2) = ... ?

Answer 20

i guess you divided by -1/2 instead of multiplying :3

Answer 21

comman misconception >.>

Answer 22

whats your new co-ordinates ?

Answer 23

1/3 ?

Answer 24

x= (2/3)*(-1/2) = -1/3
right ?
what about y ?

Answer 25

\[\sqrt3/3\]

Answer 26

you got the negative sign again :P
\(y=-\sqrt3/3\)

Answer 27

alright, that makes a lot more sense. So i can actually see where my math went wrong. Thanks a lot for clearing that up!

Answer 28

welcome ^_^