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Simplifying equation watch

    • Thread Starter

    I am quite positive that the follwing equation would simplify to 0; however, I simply can't seem to make it work

    y= (r-m)(r-n)(r-p) + (p-r)[(r-n)(r-p)+(r-m)(m-p)]

    since I originally put r=(m+n)/2, it would also become

    y=((m+n)/2-m)((m+n)/2-n)((m+n)/2-p) + (p-(m+n)/2)(((m+n)/2-n)((m+n)/2-p)+((m+n)/2-m)(m-p))

    Help, guys? Do I just have to expand everything (innumerable opportunities for mistakes)..or is there a simpler way?

    It won't be zero. eg, the first half will have a -mnp term but the second half won't (so it won't cancel).

    However, if you leave r=(m+n)/2 in, it goes to zero. You can take out a factor of ((m+n)/2-p) to make your life a bit easier.
    • Thread Starter

    Thanks - I already used the normal expansion to finally prove that it goes to zero. Wish I had seen your reply earlier
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Updated: March 15, 2008

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