Question & Answer » Mathematics Questions » In ∆ ABC, Right-Angled at B AB = 24 cm BC = 7 cm Determine (i) sin A cos A (ii) sin C cos C

In ∆ ABC, Right-Angled at B AB = 24 cm BC = 7 cm Determine (i) sin A cos A (ii) sin C cos C

Answer: To solve the question let us first understand it using a diagram.

According to the diagram if we find AC using pythagoras theorem it will be 

AC2 = AB2 + BC2

AC2 = 242 + 72

AC2 = 576 + 49

AC = √625

AC = 25

Now, 

As we know

Sin A = Side opposite to angle/hypotenuse

Sin A = BC/AC

Sin A = 7/25=0.28

Now, 

Cos A = Side adjacent to angle/Hypotenuse

Cos A = AB/AC

Cos A = 24/25 =0.96

Similarly, 

Sin C = AB/AC = 24/25 = 0.96

And Cos C = BC/AC = 7/25 = 0.28