Power of operator norm

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Why is it the case that when A is a bounded linear operator on a Hilbert space that $||A^n||$ $\leq$ $||A||^n$? I found this question which is similar but not quite the same Finite Power of Operator Norm.

EDIT: Attached picture of the operator norm I am using.enter image description here

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Hint: $\|AB\| \le \|A\| \|B\|$

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Hint : if $A,B $ are bounded linear operators, then

$$||ABx|| \le ||A||\cdot ||Bx|| \le ||A||\cdot ||B|| \cdot ||x||$$

for all $x $. Hence

$$||AB||\le ||A||\cdot ||B||. $$