NEED HELP!!! FAST!!! EXAM IN ONE HOUR xD!

[crash]

1x2(n) + 2x3 + 3x4 +...+ n(n+1)=1/3xn (n+1) x (n+2)

is this correct or not, am i doing the calculation right

n=2

2= 1/3x2 (2+1) (2+2)
2= 2/3 x 3 x 4
2= 24/3
2=8?

pls help guys i have exam in one hour and i know that this will be in the test, cause i accidentally saw the tests

 

[Denis]

24/3 = 8, not 6.
If n=2, then it's sum of 1st 2 terms, so 1*2 + 2*3 = 2 + 6 = 8
Next time you post, use * for multiplication, not x.

 

[crash]

24/3 = 8, not 6.
If n=2, then it's sum of 1st 2 terms, so 1*2 + 2*3 = 2 + 6 = 8
Next time you post, use * for multiplication, not x.

yes i know its 8, typing mistake

 

[Denis]

Show as n(2) = 8; 2 = 8 usually makes a teacher grouchy!

 

[crash]

Show as n(2) = 8; 2 = 8 usually makes a teacher grouchy!

Help me in this thread
viewtopic.php?f=16&t=42397

 

[lookagain]

..., cause i accidentally saw the tests

crash,

will your teacher accidentally score your test as a 0?