if t=3pi/2 then sin=? and cos=?

Answer 1

I am assuming that you mean what is sin(t) and cos (t)

If that's the case, then we know 2pi radians is a full circle or 360°. We can use this information to determine where our point on the circle falls.

(3pi/2 rad) * (360°/2pi rad) = 270°

This falls on the y-axis between the third and fourth quadrant so we know:

sin(3pi/2) = -1

cos(3pi/2) = 0

Answer 2

sint = -1

cost=0

3pi/2 is 270 degrees or the negative y axis