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प्रश्न
If a + b + c = 0, then \[\frac{a^2}{bc} + \frac{b^2}{ca} + \frac{c^2}{ab} =\]
विकल्प
0
1
-1
3
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उत्तर
We have to find `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)`
`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 a xx a)/(a xx b xx c))+ ((b xx b xx b)/(a xx b xx c))+((c xx c xx c)/(a xx b xx c)) = 3 `
`a^2 /(abc)+ b^2/(abc) +c^2 /(abc ) = 3`
Hence the value of `a^2 /(bc)+ b^2/(ac) +c^2 /(ab ) = 3`.
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