How do i simplify the following: $\sum_{i=1}^n (3i^2+4) - \sum_{j=2}^{n+1} (3j^2+1)$ I want to simplify

$$\sum_{i=1}^n (3i^2+4) - \sum_{j=2}^{n+1} (3j^2+1)$$

without a summation sign in the answer. How can I do this?
I can't work out how to simplify this expression. I appreciate any help.

Hint: Sometimes it helps to write the terms of a sum so you're not just looking at symbols. The sum is
\begin{align*}
(3 \cdot 1^2 + 4) + &(3 \cdot 2^2 + 4) + (3 \cdot 3^2 + 4) + \cdots + (3 \cdot n^2 + 4) \\
- \Big[ &(3 \cdot 2^2 + 1) + (3 \cdot 3^2 + 1) + \cdots + (3 \cdot n^2 + 1) + (3 \cdot (n+1)^2 + 1)\Big].
\end{align*}
Can you see how to simplify that?
