/sci/ - Science & Math

[Anonymous No.2842725]

hey /sci/

I was on wikipedia and I saw the following:
s=1+2+4+8+...
s=1+2(1+2+4+8+...)
s=1+2s
s= -1

is this right?

pic related: my face when I saw this

[Anonymous No.2842782]

bump

[Anonymous No.2842788]

Ok, I'm so high right now and that is just so mind blowing. Someone tell me what's going on. Someone.

[Life No.2842796]

If that's any series, s is just plain infinity

[Anonymous No.2842803]

The series 1+2+4+8+... is divergent.

[Anonymous No.2842810]

must have been a troll who wrote that.

[Anonymous No.2842817]

You can't use that kind of algebra with divergent series. What you found isn't mind blowing, it's just a proof by contradiction of this fact.

ie. lets assume we can use basic algebra with a divergent series. Oh shit we come to a conclusion that is obviously contradictory; therefore, we cannot use basic algebra with divergent series.

[Anonymous No.2842847]

The sum of a divergent series cannot necessarily be expressed as any number or even + or - infinity.
Consider 1, -2, 3, -4, 5...
Each odd number is paired with a negative number that is greater in magnitude than it, so the sum of the series must be -1 + -1 + -1, etc, which is -infinity.
But wait!
It can also be expressed as 1 + (-2 + 3) + (-4 + 5), ... where it's now 1+1+1+1... = infinity
So no, it's not right, it's an example to show that you can't calculate the sum of a divergent series.

[Anonymous No.2842884]

>>2842803
SIEG HEIL SIEG HEIL SIEG HEIL SIEG HEIL SIEG HEIL SIEG HEIL SIEG HEIL SIEG HEIL