The value of \( \Large \frac{ \left(x-y\right)^{3}+ \left(y-z\right)^{3}+ \left(z-x\right)^{3} }{ \left(x^{2}-y^{2}\right)^{3}+ \left(y^{2}-z^{2}\right)^{3} \left(z^{2}-x^{2}\right)^{3} } \)
Correct Answer: |
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C) \( \Large \left[ \left(x+y\right) \left(y+z\right) \left(z+x\right) \right]^{-1} \) |
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Description for Correct answer:
We know, \( \Large a+b+c=0 \)
Therefore, \( \Large a^{3+}b^{3}+c^{3} = 3abc \)
As, \( \Large \left(x^{2}-y^{2}\right)+ \left(y^{2}-z^{2}\right)+ \left(z^{2}-x^{2}\right) = 0 \)
Therefore, \( \Large \left(x^{2}-y^{2}\right)^{3}+ \left(y^{2}-z^{2}\right)^{3}+ \left(z^{2}-x^{2}\right)^{3} \)
= \( \Large 3 \left(x^{2}-y^{2}\right) \left(y^{2}-z^{2}\right) \left(z^{2}-x^{2}\right) \)
= \( \Large 3 \left(x-y\right) \left(x+y\right) \left(y-z\right) \left(y+z\right) \left(z+x\right) \left(z-x\right) \)
=\( \Large 3 \left(x-y\right) \left(y-z\right) \left(z-x\right) \left(x+y\right) \left(y+z\right) \left(z+x\right) \)
Also, \( \Large \left(x-y\right)+ \left(y-z\right)+ \left(z-x\right) = 0 \)
and \( \Large \left(x-y\right)^{3}+ \left(y-z\right)^{3}+ \left(z-x\right)^{3} = 3 \left(x-y\right) \left(y-z\right) \left(z-x\right) \)
Therfore, Given expression
= \( \Large \frac{3 \left(x-y\right) \left(y-z\right) \left(z-x\right) }{3 \left(x-y\right) \left(y-z\right) \left(z-x\right) \left(x+y\right) \left(y+z\right) \left(z+x\right) } \)
= \( \Large \left[ \left(x+y\right) \left(y+z\right) \left(z+x\right) \right]^{-1} \)
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