We are given with 90<x<180 degrees and asks for the value of sin(x/2), cos(x/2) and tan(x/2). We just substitute the maximum and minimum angle to the equations. sin (180/2) is equal to 1 and sin (90/2) is equal to [tex] \frac{ \sqrt{2} }{2} [/tex] to 1. cos (x/2) is equal to 0≤y≤[tex] \frac{ \sqrt{2} }{2} [/tex]. tan (x/2) is equal to 1 to infinity.