## Trigonometry (10th Edition)

Published by Pearson

# Chapter 8 - Complex Numbers, Polar Equations, and Parametric Equations - Section 8.1 Complex Numbers - 8.1 Exercises: 7

real, complex

#### Work Step by Step

Since $7$ is a natural number and natural numbers are a subset of the set of real numbers, $7$ is a real number. Also, for a complex number $a + bi$, if $b = 0$, then $a + bi = a$, which is a real number. Thus, the set of real numbers is a subset of the set of complex numbers. Therefore, 7 can be identified as a complex number as well.

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.