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In Delta ABC if a =2, b= 3, c = 4 th...

In ` Delta ABC if a =2, b= 3, c = 4 ` then cos A + cos B + cos C =

A

` ( 7)/( 8)`

B

` ( 11)/( 16) `

C

` - (1)/(4) `

D

` ( 21)/( 16) `

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The correct Answer is:
D
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AAKASH SERIES-PROPERTIES OF TRIANGLES-PRACTICE EXERCISE
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