# Cumulative Sum

David shared this idea 9 years ago
Under Consideration

Hi,

I think a new command should be added to Geogebra called CumulativeSum. I think this command would better serve calculus students who want to plot a sequence of partial sums of an infinite series. I suggest the command should have this option:

CumulativeSum

• That is, if the list contains:

list={a1,a2,a3,a4,a5,...,an}

Then CumulativeSum

• would produce:

{a1, a1+a2, a1+a2+a3, ... , a1+a2+a3+...+an}

Then the students could do the following: Create a slider for an integer n, then:

L1=Sequence[n]

L2=Sequence[1/k^2,k,1,n]

L3=CumulativeSum[L2]

Zip[(A,B),A,L1,B,L3]

And they would have a plot of the sequence of partial sums with ease, which they could then use to examine the convergence, divergence of infinite series.

Now, I know there are ways that this can already be done. For example.

L1=Sequence[n]

L2=Sequence[1/k^2,k,1,n]

L3=Sequence[Sum[L2,m],m,1,n]

Zip[(A,B),A,L1,B,L3]

But that is much harder for students who are just being introduced to Geogebra to understand, especially when the series go from say n=5 to infinity.

Not sure if I am making the suggestion in the right place.

D. 2

You can create your own tool.

The attached tool only uses the command

Sequence[Sum[<list>,k],k,1,Length[<list>]]

Simon

https://ggbm.at/1391091