Giá trị của Lim {{3^n} - {{5.2}^{2n/ 2.3}^n} + {2^{2n + 1là

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Giá trị của \(\mathop {\lim }\limits_{n \to + \infty } \frac{{{3^n} - {{5.2}^{2n}}}}{{{{2.3}^n} + {2^{2n + 1}}}}\) là

\[\frac{1}{2}\].

\[ - 5\].

\[\frac{3}{2}\].

\[ - \frac{5}{2}\].

Giải thích

Chọn D

Ta có \(\mathop {\lim }\limits_{n \to + \infty } \frac{{{3^n} - {{5.2}^{2n}}}}{{{{2.3}^n} + {2^{2n + 1}}}} = \mathop {\lim }\limits_{n \to + \infty } \frac{{\frac{{{3^n}}}{{{4^n}}} - 5}}{{2.\frac{{{3^n}}}{{{4^n}}} + 2}} = - \frac{5}{2}\).