Sum of infinite series of fractions with powers of 2 in denominators

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$$\frac{1}{2}+\frac{1}{4}+\cdots+\frac{1}{2^n}<1$$ How can I show this holds? I have tried adding couple of terms in photomath and it seems to hold, cannot prove it tho

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Since there is no $n$ on the right side, there is no way to induct.

What you can do is show by induction that $\frac{1}{2}+\frac{1}{4}+\cdots+\frac{1}{2^n} =1-\frac1{2^n} $ from which the conclusion immediately follows.