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In triangle ABC if cotA =(x³+x³+x)^1/2 , cotB = (x+x^-1+1)^1/2 and cotC=(x^-3+x^-2+x^-1)^1/2 then find the magnitude of angle C.

2 Answers

262

Aditya Bhutra ·2012-04-22 10:53:58

i think you meant angle B .

cotC = x^-1cotB
cotA = xcotB

for any triangle,

cotAcotB + cotBcotC + cotCcotA =1

or , (1+x+x^-1)cot²B = 1

cot⁴B=1

now it is evident that cotB=-1 is not possible (since cotB>0)

thus cotB=1 , B=45⁰

no, i meant C only.

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