2.3 ^ n + 1 + 7.3 ^ n - 1 3^ n + 2 - 2 (1/3) ^ l - n = - Vidyadip

MCQ

${{{{2.3}^{n + 1}} + {{7.3}^{n - 1}}} \over {{3^{n + 2}} - 2{{(1/3)}^{l - n}}}} = $

✓
$1$
B
$3$
C
$-1$
D
$0$

✓

Answer

Correct option: A.

$1$

a
(a) ${{{{2.3}^{n + 1}} + {{7.3}^{n - 1}}} \over {{3^{n + 2}} - 2{{\left( {{1 \over 3}} \right)}^{1 - n}}}} = {{{{2.3}^{n - 1}}{{.3}^2} + {{7.3}^{n - 1}}} \over {{3^{n - 1}}{{.3}^3} - {{2.3}^{n - 1}}}} = {{{3^{n - 1}}[18 + 7]} \over {{3^{n - 1}}[27 - 2]}} = 1$.

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