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Prove that a(b^(2) + c^(2)) cos A + b(c^...

Prove that `a(b^(2) + c^(2)) cos A + b(c^(2) + a^(2)) cos B + c(a^(2) + b^(2)) cos C = 3abc`

A

`3abc^(2)`

B

`3a^(2)bc`

C

3abc

D

`3ab^(2)C`

Text Solution

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The correct Answer is:
C
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OBJECTIVE RD SHARMA ENGLISH-PROPERTIES OF TRIANGLES AND CIRCLES CONNECTED WITH THEM-Chapter Test
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