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Math Help - related to triangles

  1. #1
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    related to triangles

    Q. AD,BE,CF are the altitudes of an acute angled triangle ABC.
    Prove that 1/AD + 1/BE > 1/CF.
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  2. #2
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    Multiply this inequality by twice the area of ABC.
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  3. #3
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    sorry , i couldn't understand. Can u please post the solved answer?
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  4. #4
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    Don't you know how to multiply both sides of an inequality by the same number? In general, if x > y and a > 0, then ax > ay. Here I am suggesting multiplying both sides by 2S where S is the area of the triangle ABC and using the fact that S = 1/2 AD * BC, and similarly for other altitudes.
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