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In A B C , if cotA+cotB+cotC=0 then fin...

In ` A B C ,` if `cotA+cotB+cotC=0` then find the value of `cosAcos BcosC`

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`cotA+cotB+cotC = 0`
`=>cosA/sinA +cosB/sinB = -cosC/sinC`
`=>(cosAsinB+sinAcosB)/(sinAsinB) = -cosC/sinC`
`=>(sin(A+B))/(sinAsinB) = -cosC/sinC`
`=>(sin(pi-C))/(sinAsinB) = -cosC/sinC`
`=>(sinC)/(sinAsinB) = -cosC/sinC`
`=>(sin^2C)/(sinAsinB) = -cosC->(1)`
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