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Math Help - Find the unknown side of a triangle?

  1. #1
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    [Solved]Find the smallest angle in a triangle?

    I'm lost in this question.

    Find the smallest angle of triangle ABC in which a:b:c = √2 : √3+1 :2
    Last edited by Tentaikansokup; November 29th 2011 at 08:06 PM.
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  2. #2
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    Re: Find the smallest angle in a triangle?

    The smallest angle will be opposite the smallest side, which side do you think is the longest?

    After you know this apply the cosine rule to find the angle.
    Last edited by pickslides; November 29th 2011 at 07:11 PM.
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    Re: Find the unknown side of a triangle?

    angle A is the smallest
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    Re: Find the unknown side of a triangle?

    Yes angle A is the smallest, therefore,

    A = \cos^{-1}\left(\frac{b^2+c^2-a^2}{2bc}\right)
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    Re: Find the unknown side of a triangle?

    Oh I see.....so that's actually nothing complicated to this question! I've always overlooked things.
    And I believe the answer is 30 degrees.

    Thank you so much!
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