Ph.D research

>>62351918
lmao, kys yourself brainlet

Nigga i did this shit in community college

>>62351918
>Ph.D research
You are kidding right? This is the kind of problems we had to solve in discrete mathematic which was the very first course in my cs education,

Kek, this is one of the easy practice problems in an intro to discrete text. Fuck off, first year CS fag.

>>62351918
The solution it's n*(n+1)!, that assertion is wrong

>>62352050
Same, except mine was calc 2. Second undergraduate math course.

>>62353342

You're probably thinking of series. I don't think calc 2 typically covers induction.

shouldn't it be i*i! ???

>>62353445
Considering "for all" is written with \emph{}, whoever typeset this is clearly a retard.

>>62352050
It's likely a Ph.D. in anthropology or psychology and he is just studying our reaction to looking at math or something. Must be a reason why he is not posting this on /sci/

Also "Linguistic programming"

File: eq.png (3KB, 275x283px) Image search: [Google]

3KB, 275x283px

isn't this calc intro?

>>62353684
You do learn series in calc. That image is a series, but the point is to prove that the identity is true via induction. Completely different goals.

>>62353701
k, via induction you start with assuming the statement is true for n-th element (where n >= 1) and try to prove it for (n+1)-th
left side is easy: sum_i=1^n+1( i*i! ) = (n+1)*(n+1)! + sum_i=1^n( i*i! )

right side: (n+1 +1)! -1 = (n+2)! - 1 = (n+2)*(n+1)! - 1 = (n+1)!-1 + (n+1)*(n+1)!
where we assumed (n+1)!-1 equals sum_i=1^n( i*i! ), thus left site equals right site for (n+1)-th element if statement if correct for n-th element

now prove it for beginning of range (n=1) and you recursively proved it for every following member:
left side: 1*1! =1
right side: 2!-1 = 1
left side equals right side

File: 150385730693.jpg (19KB, 280x270px) Image search: [Google]

19KB, 280x270px

>>62351918
ahahahah

>>62353684
Why is

(i+1)*i! the same as (i+1)! in your pic? and how does that turn into the second to last line? Many years since I had calc and have not used it after uni...

>>62354411

n! = n(n-1)(n-2) ... (2)(1)

(n+1)! = (n+1)n(n-1)(n-2) ... (2)(1) = (n+1) * n!

>>62354473
Stupid me, I was reading it like this:

3!*2! = (3*2*1)*(2*1)