\(\mathop {\lim }\limits_{x \to \pm \infty } \dfrac{{2x\sqrt {{x^2} + x} - \sqrt {9{x^2} + 1} }}{{\left( {2x + 1} \right)\left( {x - 2} \right)}}\)
A.\(\mathop {\lim }\limits_{x \to \pm \infty } \dfrac{{2x\sqrt {{x^2} + x} - \sqrt {9{x^2} + 1} }}{{\left( {2x + 1} \right)\left( {x - 2} \right)}} = \dfrac{1}{2}\)
B.\(\mathop {\lim }\limits_{x \to + \infty } \dfrac{{2x\sqrt {{x^2} + x} - \sqrt {9{x^2} + 1} }}{{\left( {2x + 1} \right)\left( {x - 2} \right)}} = \dfrac{1}{2}\), \(\mathop {\lim }\limits_{x \to - \infty } \dfrac{{2x\sqrt {{x^2} + x} - \sqrt {9{x^2} + 1} }}{{\left( {2x + 1} \right)\left( {x - 2} \right)}} = - \infty\).
C.\(\mathop {\lim }\limits_{x \to + \infty } \dfrac{{2x\sqrt {{x^2} + x} - \sqrt {9{x^2} + 1} }}{{\left( {2x + 1} \right)\left( {x - 2} \right)}} = \dfrac{1}{2}\), \(\mathop {\lim }\limits_{x \to - \infty } \dfrac{{2x\sqrt {{x^2} + x} - \sqrt {9{x^2} + 1} }}{{\left( {2x + 1} \right)\left( {x - 2} \right)}} = - 1\).
D.\(\mathop {\lim }\limits_{x \to + \infty } \dfrac{{2x\sqrt {{x^2} + x} - \sqrt {9{x^2} + 1} }}{{\left( {2x + 1} \right)\left( {x - 2} \right)}} = 1\), \(\mathop {\lim }\limits_{x \to - \infty } \dfrac{{2x\sqrt {{x^2} + x} - \sqrt {9{x^2} + 1} }}{{\left( {2x + 1} \right)\left( {x - 2} \right)}} = - 1\).

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