Look at the following sum:

[tex]\[ 1 + \frac{1}{2} + \frac{1}{4} + \frac{1}{8} + \frac{1}{16} + \frac{1}{32} + \frac{1}{64} \ldots \][/tex]

Notice that the denominator of each fraction is twice the denominator that comes before it.

If you continue adding on fractions, do you reach a sum of 2?



Answer :

Let's analyze the given infinite series and determine if its sum approaches 2:

[tex]\[ 1 + \frac{1}{2} + \frac{1}{4} + \frac{1}{8} + \frac{1}{16} + \frac{1}{32} + \frac{1}{64} + \cdots \][/tex]

This is a geometric series where each term after the first is obtained by multiplying the preceding term by a common ratio. In this case, the first term [tex]\( a \)[/tex] is 1, and the common ratio [tex]\( r \)[/tex] is [tex]\(\frac{1}{2}\)[/tex].

To find the sum of an infinite geometric series, we use the formula:

[tex]\[ S = \frac{a}{1 - r} \][/tex]

where
- [tex]\( S \)[/tex] is the sum of the series,
- [tex]\( a \)[/tex] is the first term,
- [tex]\( r \)[/tex] is the common ratio, and the series will converge if [tex]\( |r| < 1 \)[/tex].

Here, [tex]\( a = 1 \)[/tex] and [tex]\( r = \frac{1}{2} \)[/tex].

Let's plug these values into the formula:

[tex]\[ S = \frac{1}{1 - \frac{1}{2}} \][/tex]

Simplify the denominator:

[tex]\[ 1 - \frac{1}{2} = \frac{1}{2} \][/tex]

Thus, the sum of the series is:

[tex]\[ S = \frac{1}{\frac{1}{2}} = 2 \][/tex]

So, the sum of the infinite series [tex]\( 1 + \frac{1}{2} + \frac{1}{4} + \frac{1}{8} + \cdots \)[/tex] indeed approaches 2.