If cos(t)=−9/11 where pi
cos(2t) =
sin(2t)=
cos(t/2)=
sin(t/2)=

Sin ( t ) = √ ( 1 - (-9/11)²) = √ ( 1 - 81/121 )= √ 40/121
sin ( t ) = - 2 √10 / 11
cos ( 2 t ) =  cos² t - sin² t  =  81/121  - 40 / 121  =  41 /121
sin ( 2 t ) = 2 sin t cos t = 2 · ( - 2 √10/11 ) · ( - 9 /11 ) = 36√10 / 121
cos ( t/2 ) = √( 1 + cos t ) / 2 = 1 /√11
sin ( t/2 ) = √( 1 - cos t ) / 2 = √( 10/11 )

Step-by-step explanation:

Ok, this problem is on construction in mathematics.

also, see attached a rough sketch of the two constructions.

The similarities, as can be seen, is that for both constructions, we need to two major points to obtain a bisector, for the line segment the major points are (A and B) and for the angle segment the points are(P and Q)

The difference between the two construction is that the line segment needs basically two bisectors to equally divide the line located at (O and P), while the angle segment needs just one bisector at (O) to bisect the angle.