Question

Plz answer This.................. :)

Answer 1

$\bold{\underline{Hey\: Mate\: !}}$

$\bold{\underline{Revise \:formula \:\colon}}$

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$\bold{x^{3} - y^{3} = (x-y)[x^{2} + xy + y^{2}]}$

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$1)\:\bold{\large{\frac{987\times987\times987\: + 357\times 357\times357}{987\times987 \: + \: 987\times357 + 357\times 357}}}$

General exponential function :

$1)\:\bold{\large{\frac{987^{3}\: - \:357^{3}}{987^{2} \: + 987 \times 357 \: +\: 357^{2}}}}$

Let ,

a = 987

b = 357

$\implies \frac{a^{3} \: - \: b^{3}}{a^{2} \: +\: ab \: + b^{2}}$

$\implies \frac{ (a \: - \: b)(a^{2} + ab + b^{2} )}{(a^{2} + ab + b^{2})}$

We are getting this equation now substitute it :

$\implies \frac{ (a \: - \: b)\cancel{(a^{2} + ab + b^{2} )}}{\cancel{(a^{2} + ab + b^{2})}}$

After substitution we get

$\implies [ a \: - \: b ]$

Put the value of a & b

$\implies [987 \: - \:357]$

$\bold{\boxed{ Answer = 630}}$

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That means option $\:\bold{(C)}$ is correct.

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$\bold{Thanks}$