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A First Course in Mathematical Analysis - D. Brannan. Rules added as they may be needed. Reciprocal Rule Page 10. For any positive $a,b$ $a < b Leftrightarrow frac{1}{a} > frac{1}{b}$ Power rule: page 10. for any non-negative $a,b$ and $p > 0$ $a < b Leftrightarrow {a^p} < {b^p}$ . page 59. Deduce: $mathop {lim }limits_{n to infty } {a^{{textstyle{1 over n}}}} = 1$ Soln. If $a > 1$ we can write $a = 1 + c$ where $c > 0$ . Then $1 le {a^{1/n}} = {(1 + c)^{{textstyle{1 over n}}}} le 1 + frac{c}{n}$ for $n = 1,2,...$ The soln. continues... Please explain how (from the book) we get LHS inequality ( $1 le {a^{{textstyle{1 over n}}}}$ ).
real-analysis