If in a triangle a `cos^2C/2+cos^2A/2=(3b)/2,` then find the relation between the sides of the triangle.

If in a triangle a `cos^2C/2+cos^2A/2=(3b)/2,` then find the relation between the sides of the triangle.

Monjur Alahi

4 views

2025-01-04 04:42

1 Answers

Salim Ahmed Kawsar

`a cos^(2).(C)/(2) + cos^(2).(A)/(2) = (3b)/(2)`
or `a (1 + cos C) + c (1 + cos A) = 3b`
or `a+c + (a cos C + c cos A) = 3b`
or `a + c + b = 3b` [bt the projection formula]
or `a + c = 2b`
Hence, a, b, c and in A.P.

4 views Answered 2023-02-05 15:29

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