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Question
Evaluate:
253 − 753 + 503
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Solution
In the given problem we have to evaluate the following
Given 253 − 753 + 503
We shall use the identity `a^3 + b^3 +c^3 -3abc = (a+b+c)(a^2 + b^^2 + c^2 - ab - bc - ca)`
Let Take a = 25,b = 75,c = 50
`a^3 + b^3 + c^3 (a+b+c) (a^2+b^2 + c^2 - ab - bc -ca)`
` a^3 + b^3 + c^3 = (a+b+c)(a^2 + b^2 + c^2 -ab - bc-ca) + 3abc`
`a^3 + b^3+ b^3 = (-75 + 25 -50)(a^2 + b^2 + c^2 - ab =bc - ca) + 3abc`
`a^3 + b^3 + c^3 = 0 xx (a^2 + b^2 c^2 - ab - bc - ca) + 3abc`
`a^3+ b^3+c^3 = +3abc`
`25^3 - 75^3+50^3 = 3 xx 25 xx 50 xx -75`
` = -281250`
Hence the value of 253 − 753 + 503 is` -281250`.
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