2026 AHS P2 Q11

Given that \(\sin A=\dfrac5{13}\), where \(0\le A\le\dfrac\pi2\) and \(\cot B=-\dfrac{24}{7}\), where \(\dfrac\pi2\le B\le\pi\), without solving for \(A\) and \(B\), find the exact value for

1. \(\cos B\),[1]
2. \(\sec A\),[2]
3. \(\sin(A+B)\)[2]