Caesar uttered “Et tu, Brute!” in shock and betrayal when he saw Brutus, his trusted friend, among the conspirators. It reflected his heartbreak and disbelief that Brutus would conspire against him.
Explanation: The phrase highlights Caesar’s emotional agony, as Brutus’s betrayal hurt him more than the physical act of assassination.
In the adjoining figure, $\triangle CAB$ is a right triangle, right angled at A and $AD \perp BC$. Prove that $\triangle ADB \sim \triangle CDA$. Further, if $BC = 10$ cm and $CD = 2$ cm, find the length of AD. 
In the adjoining figure, TP and TQ are tangents drawn to a circle with centre O. If $\angle OPQ = 15^\circ$ and $\angle PTQ = \theta$, then find the value of $\sin 2\theta$. 