Parametric equations -_-?

Question

True or false: The parametric curve x= 2cos(-t), y=2sin(-t), 0 (< or equal to) t (< or equal to) 2pi is traced clockwise.

do i determine this by the negative t?

can somebody please help me through it, because my book doesn't explain anything. it just has examples

Answer 1

x = 2cos(t) y = 2sin(t) is circle of radius 2. As we increase t from 0 to 2pi (0 to 360 degrees) we get the x and y values in the counter-clockwise direction.

A negative angle spins in the other direction so it is indeed spinning clockwise.

x= 2cos(-t), y=2sin(-t)

A negative angle(&gt;360 can be converted to it&#039;s congruent positive angle by adding 360, so -10 degrees is 350 degrees, -90 is 270, -180 is 180, etc.