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In triangle ABC, if cos^(2)A + cos^(2)B ...

In triangle ABC, if `cos^(2)A + cos^(2)B - cos^(2) C = 1`, then identify the type of the triangle

Text Solution

Verified by Experts

The correct Answer is:
Right angled triangle
`cos^(2) A + cos^(2) B - cos^(2) C = 1`
or `1 - sin^(2) A + 1 - sin^(2) B - 1 + sin^(2) C = 1`
or `sin^(2) A + sin^(2) B = sin^(2) C rArr a^(2) + b^(2) = c^(2)`
Thus, the triangle is right angled at C
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