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Ex 8.1, 6 - If Angle A and Angle B	are acutes angles  such that cos A = cos b, then show that Angle A = Angle B

Ex 8.1, 6 - Chapter 8 Class 10 Introduction to Trignometry - Part 2

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Ex 8.1, 6 If A and B are acute angles such that cos A = cos B, then show that A = B. cos A = (Side adjacent of angle A) / Hypotenuse = AC/AB Similarly, cos B = (Side adjacent of angle A) / Hypotenuse = BC/AB Now it is given that cos A = cos B AC/AB = BC/AB AC = BC We know that in a triangle, angles opposite equal sides are equal B = A Hence proved.

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Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.