2

In the diagram K, P, T and M are points on the smaller circle.

KP KT and RPT = 90°.

RKT, QKM, QRS and SMT are straight lines.

P

eta_{b}

12 23 3

R

123

K

+

2

1

4

T

2

4

M

S

Show, with reasons, that PRST is a cyclic quadrilateral.