SOLUTION: If a^3-b^3=1343 and a-b=17, find the numerical value of ab

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Question 344686: If a^3-b^3=1343 and a-b=17, find the numerical value of ab
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If a^3-b^3=1343 and a-b=17, find the numerical value of ab
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(a^3-b^3)/(a-b) = a^2+ab+b^2
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So, a^2+ab+b^2 = 1343/17 = 79
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And (a-b)^2 = a^2-2ab+b^2 = 17^2 = 289
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Then (a^2-2ab+b^2)-(a^2+ab+b^2) = 289-79 = 210
-3ab = 210
ab = -70
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Cheers,
Stan H.
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