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Question
If a + b + c = 0, then write the value of \[\frac{a^2}{bc} + \frac{b^2}{ca} + \frac{c^2}{ab}\]
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Solution
We have to find the value of `a^2/(bc) + b^2/(ca) +c^2/(ab)`
Given `a+b+c = 0`
Using identity `a^3 +b^3 +c^3 - 3abc = (a+b+c) (a^2 +b^2 +c^2 - ab - bc - ca)`
Put `a+b +c = 0`
`a^3 +b^3 +c^3 - 3abc = (0)(a^2 +b^2 +c^2 - ab - bc - ca)`
`a^3 +b^3 + c^3 - 3abc = 0`
`a^3 +b^3 + c^3 = 3abc `
`a^3/(abc) + b^3/(abc) + c^3/(abc) = 3`
`(a xx axx a)/(abc) +(b xx bxx b)/(abc) +(c xx cxx c)/(abc) =3`
`a^2/bc +b^2/ac +c^2 /ab=3`
Hence the value of `a^2/(bc) + b^2/(ac) +c^2/(ab)` is 3.
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