Skip to main content
Ch. 5 - Complex Numbers, Polar Coordinates and Parametric Equations
Blitzer - Trigonometry 3rd Edition
Blitzer3rd EditionTrigonometryISBN: 9780137316601Not the one you use?Change textbook
Chapter 5, Problem 3

In Exercises 1–8, add or subtract as indicated and write the result in standard form. (3 + 2i) − (5 − 7i)

Verified step by step guidance
1
Identify the problem as the subtraction of two complex numbers: \((3 + 2i) - (5 - 7i)\).
Recall that to subtract complex numbers, subtract their real parts and their imaginary parts separately.
Subtract the real parts: \(3 - 5\).
Subtract the imaginary parts: \(2i - (-7i)\), which simplifies to \(2i + 7i\).
Combine the results to write the answer in standard form \(a + bi\), where \(a\) is the real part and \(b\) is the coefficient of \(i\).

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
1m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Complex Numbers and Standard Form

Complex numbers are expressed in the form a + bi, where a is the real part and b is the imaginary part. The standard form means writing the result explicitly as a sum of a real number and an imaginary number.
Recommended video:
04:47
Complex Numbers In Polar Form

Addition and Subtraction of Complex Numbers

To add or subtract complex numbers, combine their real parts and their imaginary parts separately. For example, (a + bi) − (c + di) = (a − c) + (b − d)i.
Recommended video:
3:18
Adding and Subtracting Complex Numbers

Imaginary Unit i and Its Properties

The imaginary unit i is defined as the square root of -1, with the property i² = -1. Understanding this helps in simplifying expressions involving imaginary parts.
Recommended video:
2:20
Imaginary Roots with the Square Root Property