I need help with this question,
a) express in polar co-cordinates the cartesian co-ordinates (2, -6)
b) express in cartesian co-ordinates the polar co-cordinates (3, 150degrees)
For these types of problems you need to recall that:Originally Posted by simon
Inverting these relations gives:
So for question a)
(2,-6) => x = 2, y = -6
is a reference angle. The point (2,-6) is in the 4th quadrant, so your angle measured from the +x axis is 360 - 71.5651 = 288.435 degrees.
Thus: (2,-6) => (2sqrt(10), 288.435 degrees).
For question b)
(3, 150 degrees) => r = 3, = 150 degrees
Thus: (3, 150 degrees) => (-2.59808, 1.5).
(And note that it is, in fact, in the second quadrant as the original coordinates state.)