What is the length of the chord of a unit circle which subtends an angle $$\theta$$ at the centre?

What is the least value of $$25\cos e{c^2}x + 36{\sec ^2}x$$ ?

What is the value of $${{\sin 34^\circ \cos 236^\circ - \sin 56^\circ \sin 124^\circ } \over {\cos 28^\circ \cos 88^\circ + \cos 178^\circ \sin 208^\circ }}$$ ?

tan54$$^\circ$$ can be expressed as