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If in a triangle, a cos ^(2)""C/2+c cos ...

If in a triangle, `a cos ^(2)""C/2+c cos ^(2)""A/2=(3b)/(2),` then its sides will be in-

A

are in G.P.

B

are in H.P.

C

satisfy a + b=c

D

are in A.P.

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