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If in `Delta ABC`, sides a, b, c are in A.P. thenA. `B gt 60^(@)`B. `B lt 60^(@)`C. `B le 60^(@)`D. `B = |A - C|`

Answer» Correct Answer - C
`2b = a + c rArr 2 sin B = sin A + sin C`
or `4 sin.(B)/(2) cos.(B)/(2) = 2 sin ((A +C)/(2)) cos ((A -C)/(2))`
`rArr sin ((B)/(2)) = (1)/(2) cos (A - C) le (1)/(2) rArr B le 60^(@)`


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