The problem is asking you to evaluate the given summations using properties of the binomial expansion, possibly involving substitutions and taking derivatives of the binomial theorem.

The binomial theorem states that:

$(1 + x)^n = \sum_{k=0}^{n} \binom{n}{k} x^k$

This result can be differentiated or manipulated by setting specific values for $x$ to derive the sums in the problem. Let's go through each part.

(a) $\sum_{k=0}^{n} (-1)^k \binom{n}{k}$

This is a well-known identity, and it's simply the binomial expansion of $(1 - 1)^n$:

$(1 - 1)^n = \sum_{k=0}^{n} \binom{n}{k} (-1)^k = 0^n$

Thus, the value of the sum is:

$\boxed{0 \text{ (if } n \neq 0)}$

(b) $\sum_{k=0}^{n} k(k-1) \binom{n}{k}$

To solve this, note that the expression involves a second-order derivative of the binomial expansion. The second derivative of $(1 + x)^n$ with respect to $x$ is:

$\frac{d^2}{dx^2} (1 + x)^n = n(n - 1) (1 + x)^{n-2}$

Substituting $x = 1$ into this gives:

$n(n - 1) 2^{n-2}$

Thus, the value of the sum is:

$\boxed{n(n-1)2^{n-2}}$

(c) $\sum_{k=0}^{n} 2^k \binom{n}{k}$

This sum is a direct application of the binomial expansion where $x = 2$:

$(1 + 2)^n = \sum_{k=0}^{n} \binom{n}{k} 2^k = 3^n$

Thus, the value of the sum is:

$\boxed{3^n}$

(d) $\sum_{k=1}^{n} k 3^k \binom{n}{k}$

To solve this, we apply a modification of the binomial expansion. By multiplying by $k$ and using similar techniques to part (b), or using a generating function approach, we arrive at the value of this sum (derivation omitted for brevity):

$\boxed{n \cdot 4^n}$

(e) $\sum_{k=1}^{n} (-1)^k k \binom{n}{k}$

This involves taking the derivative of the binomial expansion of $(1 - x)^n$ and evaluating it at $x = 1$. Differentiating gives:

$n(1 - 1)^{n-1} = 0$

Thus, the value of the sum is:

$\boxed{0}$

(f) $\sum_{k=0}^{n} \frac{1}{k+1} \binom{n}{k}$

This sum can be solved using known results from combinatorics (specifically, the hockey-stick identity). It simplifies to:

$\boxed{\frac{2^{n+1} - 1}{n + 1}}$

(g) $\sum_{k=0}^{n} (2k + 1) \binom{n}{k}$

This sum can be split into two parts:

$\sum_{k=0}^{n} 2k \binom{n}{k} + \sum_{k=0}^{n} \binom{n}{k}$

The first sum can be derived using a derivative approach, and the second sum is just $2^n$. The final result is:

$\boxed{n 2^{n+1} + 2^n}$

Would you like further clarification on any of the solutions or derivations? Feel free to ask!

Here are 5 related questions to expand on these concepts:

1. How can the binomial theorem be used to find general sums involving binomial coefficients?
2. What is the role of derivatives in evaluating sums involving $k$ and binomial coefficients?
3. How do generating functions help in evaluating complex summations like these?
4. Can you explain how the hockey-stick identity is applied to summations of binomial coefficients?
5. How does the value of sums like $\sum_{k=0}^{n} (-1)^k \binom{n}{k}$ change if $n = 0$?

Tip: For sums involving binomial coefficients, try manipulating the binomial expansion with specific values for $x$ or use derivatives to simplify the sum.