- #1
UniPhysics90
- 16
- 0
I'm following a worked example and really don't get a certain step in it: the step is going between
r=(-(s-2a)sin($) , scos($))
and
(r^2)=(s^2)+(4(a^2)-4as)sin($)
First of all how do you 'square' coordinates? I would have though it stays as coordinates?
Even when i try different ways of multiplying it out i can't get this answer, i always end up with extra terms or wrong coefficients.
any help would be great.
thanks
r=(-(s-2a)sin($) , scos($))
and
(r^2)=(s^2)+(4(a^2)-4as)sin($)
First of all how do you 'square' coordinates? I would have though it stays as coordinates?
Even when i try different ways of multiplying it out i can't get this answer, i always end up with extra terms or wrong coefficients.
any help would be great.
thanks