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Cool goIITian

total posts: 31
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Hi !

the ans for yur 1qes. is k=3and not k=1

it was difficult typing the solution specially pie and theta but i have manage to do it

check it out............

tan x+tan[x+(pie) /3]+tan[x -(pie) /3]

=tan x+[{tan x +tan(pie)/3}/(1- tan x tan(pie)/3)] +[{tan x -tan(pie)/3}/(1+tan x tan(pie)/3)]

= tan x+ [tan x+ tan²x tan(pie)/3+ tan(pie)/3+ tan²(pie)/3 tan x+

tanx - tan²x tan(pie)/3- tan(pie)/3+ tan²(pie)/3 tan x] /{1- 3tan² x}

= [ tan x- 3tan³ x+2 tan x+6 tan x] / {1- 3tan²x}

= 3 [3tan x - tan³x] / {1- 3tan² x}

= 3tan3x

tan x+tan[x+(pie)/3]+tan[x-(pie)/3]=k tan3x

there fore

tan x +tan[x+(pie)/3]+tan[x-(pie)/3]=3 tan3x

k=3

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