Question

I need help with math I have dyscalculia and I don’t understand

Answer 1

The summation symbol means that we need to add the terms (n-1) for n = 1, 2, 3, and 4.

In other words, we have the following terms:

`\begin{gathered} 1-1=0 \\ \\ 2-1=1 \\ \\ 3-1=2 \\ \\ 4-1=3 \end{gathered}`

And we need to add them:

`0+1+2+3=6`

Therefore, the result is 6.