max value

if k>1/2 so it could be any number
the the max value could be infinite when k->∞
so please re check ur ques

made the changes,and the options depend on k

2cos(A+B/2)cos(A-B)/2+kcosC
this will be maximum when A and are both 60° each
so u get √3+kcosC
AS IT IS A TRIANGLE SO A+B+C=∩
hence C=60°

answer must be √3+k√3/2

GRAPH[12][12][12]

THEORETICALLY PASAND NAHIN AAYA KYA[7]

hmmmmmmmmmmmnnnnnnnnnnn

1st point equality is not given in the question

2nd why arent we getting the same answers[7]
if u find a flaw in my solution do post it!!!!!!!!![1]

so maximum value is 3/2 .....dont understand y u posted ur first """point""

but in the answer given max value only depends on K not cosC

I AGREE WITH U VIVEK
PLEASE SEE #4

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http://www.goiit.com/posts/list/algebra-if-a-b-c-pi-then-maximum-value-of-cosa-cosb-kcosc-where-912480.htm

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