Let's analyze the problem.

Given Information:

• The vector $\overrightarrow{AB} = a$.
• We need to express $\overrightarrow{CD}$ in terms of $a$.

Step-by-Step Solution:

1. Observe that $\overrightarrow{AB}$ is given in the diagram.
2. Look at $\overrightarrow{CD}$ and compare its direction and magnitude with $\overrightarrow{AB}$.
3. If $\overrightarrow{CD}$ follows the same direction and magnitude as $\overrightarrow{AB}$, then $\overrightarrow{CD} = a$.
4. If $\overrightarrow{CD}$ is in the opposite direction or is a multiple of $a$, we adjust accordingly.

By checking the image, it looks like $\overrightarrow{CD}$ follows the same direction and magnitude as $\overrightarrow{AB}$, so:

$\overrightarrow{CD} = a$

Would you like a more detailed breakdown? Here are some related questions to deepen your understanding:

Related Questions:

1. What are the properties of vector addition and subtraction?
2. How do we determine if two vectors are equal?
3. How do we represent vectors using coordinates?
4. What is the difference between displacement vectors and position vectors?
5. How do we find the magnitude of a vector?

Tip:

Always check if two vectors have the same direction and magnitude before concluding their equivalence.