- #1
enian
- 23
- 0
This problem is from Apostol's Caclulus book vol 1 page 35 or 36 #2
Show that
1 - 4 = -(1 + 2)
1 - 4 + 9 = 1 + 2 + 3
1 - 4 + 9 - 16 = -(1 + 2 + 3 + 4)
is true by mathematical in duction
I get to this step but have problem figuring out how to finish it off
-1^(n+1) * n^2 = -1^(n+1) * (n(n+1)/2)
I then do the plugging in bit and end up with
-1^(n+1) * (n(n+1)/2) + (-1^(n+2) * (n+1)^2) << the next term (n+1)
I have tried to work this out a few times but I can't seem to get a stable answer, any helps? Maybe I've forgotten some simple algebra tricks. The answer I think should look like
-1^(n+2) * ((n+1)(n+2)/2)
Show that
1 - 4 = -(1 + 2)
1 - 4 + 9 = 1 + 2 + 3
1 - 4 + 9 - 16 = -(1 + 2 + 3 + 4)
is true by mathematical in duction
I get to this step but have problem figuring out how to finish it off
-1^(n+1) * n^2 = -1^(n+1) * (n(n+1)/2)
I then do the plugging in bit and end up with
-1^(n+1) * (n(n+1)/2) + (-1^(n+2) * (n+1)^2) << the next term (n+1)
I have tried to work this out a few times but I can't seem to get a stable answer, any helps? Maybe I've forgotten some simple algebra tricks. The answer I think should look like
-1^(n+2) * ((n+1)(n+2)/2)