Question

if angle a and angle b are acute angles such that cos a equal to cos b then show that angle a is equal to angle b​

Answer 1

Let;

cosA = side adjacent A/Hypotenuse = AC/AB

cosB = side adjacent B/Hypotenus = BC/AB

Given that

cosA = cosB

AC/AB = BC/AB

AC = BC

In triangle, angles opposite equal side are equal

∠B=∠A

Answer 2

According to the question:-

Let cosA=   side adjacent A/ Hypotenuse

AC/AB

Similarly,

cosB=  side adjacent B /Hypotenuse

BC/AB

Given that

cosA=cosB

AC/AB=BC/AB

AC=BC

In triangle,

angles opposite equal side are equal  

∠B=∠A

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