Find a value for \(a\) such that the \(\lim{x\to x^{2}-x^{2}+x}\over{x-x^{2}+2x^{2}}=3\)[limit as \(x\) approaches infinity of the fraction with numerator ax to the fifth minus \(x\) cubed plus \(x\) and denominator x minus x cubed plus 2 x to the fifth equals 3].
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