Q1 of 87 Page 10

Find the area of the triangle ∆ABC in which a = 1, b = 2 and ∠c = 60o.

Given,



a=1, b=2 and ∠C=60°


By Cosine law,




2=1+4-c2


c2 =5-2


c2 =3






By Heron’s Law,


Area of Triangle,





sq. units


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