In triangle ABC, right angled at B, AB = 24 cm, BC = 7 cm. Determine : (i) Sin A, Cos A (ii) Sin C, Cos C

Solution :

Let us draw a right \(\triangle\) ABC,

By using Pythagoras Theorem, we have :

\({AC}^2\) = \({AB}^2\) + \({BC}^2\) = \((24)^2\) + \((7)^2\)

= 576 + 49 = 625

So,  AC = \(\sqrt{625}\) = 25 cm

(i)  Sin A = \(BC\over AB\) = \(7\over 25\),  Cos A = \(AB\over AC\) = \(24\over 25\)

(ii)  Sin C = \(AB\over AC\) = \(24\over 25\),  Cos C = \(BC\over AC\) = \(7\over 25\)