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In an acute angle triangle ABC, AD, BE a...

In an acute angle triangle ABC, AD, BE and CF are the altitudes, then `(EF)/a+(FD)/b+(DE)/c` is equal to -

Text Solution

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`(FE)/(a) + (FD)/(b) + (DE)/(c) = (a cos A)/(a) + (b cos B)/(b) + (c cos C)/(a)`
`= cos A + cos B + cos C`
`le (3)/(2)`
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