Question

A triangle ABC, a=7cm,b=4cm ,c=5cm. Find the value of:
a)cos A
b)sin A​

Answer 1

Answer: Step-by-step explanation:

7²=4²+5² ⇒ a²=b²+c² ⇒ ∠A=90°

a)cos A=cos 90°=0

b)sin A​ =sin 90°=1