Question

please tell step by step​

Answer 1

Answer:

pls check it. hope this is correct

Answer 2

Step-by-step explanation:

A/Q :-

$\frac{(7 {}^{n + 2}) - (6 \times 7 {}^{n + 1}) }{(21 \times 7 {}^{n}) - (2 \times 7 {}^{n + 1} ) } \\ \\ = \frac{7 {}^{n + 2 } -6 \times 7 {}^{n + 1} }{21 \times 7 {}^{n} - 2 \times 7 {}^{n + 1} } (remove \: unnecessary \: parentheses) \\ \\ = \frac{(7 - 6) \times 7 {}^{n + 1} }{(21 - 2 \times 7) \times 7 {}^{n} } (factorise \: the \: expression \: to \: make \: the \: calculation \: easier) \\ \\ = \frac{1 \times 7 {}^{n + 1} }{7 \times 7 {}^{n} } \\ \\ = \frac{7 {}^{n + 1} }{7 {}^{1} \times 7 {}^{n} } \\ \\ = \frac{7 {}^{n + 1} }{7 {}^{n + 1} } (since \: a {}^{m} \times a {}^{n} = a {}^{m + n} ) \\ \\ = 1$

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