Evaluating the six trigonometric function question attached

If tan theta is -1, we know immediately that theta is in either Quadrant II or Q IV.  We need to focus on Q IV due to the restrictions on theta.

Because tan theta is -1, the ray representing theta makes a 45 degree angle with the horiz axis, and a 45 degree angle with the negative vert. axis.  Thus the hypotenuse, by the Pythagorean Theorem, tells us that the hyp is sqrt(2).
Thus, the cosine of theta is adj / hyp, or +1 / sqrt(2), or [sqrt(2)]/2

The secant of theta is the reciprocal of that, and thus is

   2            sqrt(2)
* = sqrt(2)    (answer)
 sqrt(2)      sqrt(2)  

3π/2 < θ < 2π    is another way to say θ is in the IV quadrant.

now, the only time the tangent is 1 or -1, is right in the middle of the quadrant, in this case, that'd be at θ = 7π/4.