Question 29Points $A,$ $B$ and $C$ on a circle of radius $r$ are situated so that $AB=AC,$ $AB\gt r,$ and the length of minor arc $\overset{\frown}{BC}$ is $r.$ If angles are measured in radians, then $\frac{AB}{BC}=$ $\frac12\csc\frac14$$2\cos\frac12$$4\sin\frac12$$\csc\frac12$$2\sec\frac12$
