Question

cot°C tanite + cot-')​

Answer 1

Let A , B and C are angle of triagle

Hence, sum of all angle of triangle= 180 °

Since,

<A + <B + <C = 180 °

<A + <B = 180° - <C

take cot on both side

we get ,

cot ( A + B ) = cot ( 180° - C)

cot ( A + B ) = - cotC

we know that ,

cot ( A + B ) = cotA * cotB - 1 / cotA + cotB

since, using this formula

cotA* cotB - 1 / cotA + cotB = - cotC

cotA* cotB - 1 = - ( cotA* cotC ) -( cotB * cotC)

cotA * cotB + cotA* cotC + cotB * cotC = 1

since, here prooved ♻

cotA* cotB + cotB* cotC + cotC * cotA = 1

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Answer 2

$\boxed{Explained\:Answer}$

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