# 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 = $$BC\over AC$$ = $$7\over 25$$