sin θ=0 and cos θ=-1
Please explain in depth I have no idea how this works
well draw a coordinate system
in quadrant 1, x is + and y is +,so sin + and cos +
quad 2 x is - and y is + so sin + and cos -
quad 3 x is - and y is - so sin - and cos -
quad 4 x is + and y is - so sin - and cos +
so
we are in quad 2 or 3 where cos is -
if sin is 0, y is 0 so we are on the -x axis
there if x = -a , y = 0 then cos = -a /sqrt(a^2+0^2) = -1
caramba, theta = 180 degrees or pi radians