Sum of 2^N Sequence from 1-50: Solving Sigma Notation Problem

[reliquator]

Okay, I think this problem relates with sigma notation (I'm not good at it)

the sequence given is 2, 4, 8, 16, 32 ...

It wants you to find the sum from 1-50

So the equation thing is 2^N?

How do you find all the sums again...? Thanks

 

[Tide]

Write out the sum:

$$S = 2 + 2^2 + \cdot \cdot \cdot + 2^{50}$$

If you multiply the sum by 2 you get

$$2S = 2^2 + 2^3 + \cdot \cdot \cdot + 2^{50} + 2^{51}$$

What happens when you subtract the first equation from the second? Can you determine from that what the sum is?

 

[dextercioby]

If you mean something like

$$S=\sum_{k=1}^{50} 2^{k} =...?$$

, i guess the notation shouldn't be too difficult to grasp.
I hope.

Daniel.