## What is an R Matrix?

a) A two-dimensional data structure that stores elements of the same type

b) A list of vectors

c) A method for plotting data

d) A collection of data frames

### Answer:

a) A two-dimensional data structure that stores elements of the same type

### Explanation:

A matrix in R is a two-dimensional data structure that stores elements of the same type, organized into rows and columns. Matrices are useful for mathematical computations, especially those involving linear algebra, and for organizing data that fits into a grid-like structure.

```
# Creating a matrix in R
my_matrix <- matrix(1:6, nrow = 2, ncol = 3)
# Printing the matrix
print(my_matrix)
# Output:
# [,1] [,2] [,3]
# [1,] 1 3 5
# [2,] 2 4 6
```

In this example, a matrix named `my_matrix`

is created with 2 rows and 3 columns, filled with the numbers 1 to 6. Matrices are useful for a variety of applications, including statistical analysis and data visualization.

Matrices are a fundamental part of R’s capabilities in handling structured data and performing complex mathematical operations efficiently.