### Learn math, science, English SAT & ACT from

high-quaility study
videos by expert teachers

##### Thank you for watching the preview.

To unlock all 5,300 videos, start your free trial.

# Adding and Subtracting Complex Numbers - Concept

###### Carl Horowitz

###### Carl Horowitz

**University of Michigan**

Runs his own tutoring company

Carl taught upper-level math in several schools and currently runs his own tutoring company. He bets that no one can beat his love for intensive outdoor activities!

Subtracting and **adding complex numbers** is the same idea as combining like terms. In an expression, the coefficients of i can be summed together just like the coefficients of variables. If an expression has real numbers and square roots of negative numbers, rewrite using i and then combine like terms.

Adding and subtracting complex numbers. So if you think back to how we work with any normal number, we just add and when you add and subtract. We just combine like terms. So with this example up here 8x-4+3x+2. If I said simplify this out you would just combine like terms. So we have our 8x and our 3x, this become 11x. -4+2 just becomes -2. You combine like terms. When you're dealing with complex and imaginary numbers, it's really no different. Okay? So here I have a problem 4i-3+2. I can just combine my imaginary numbers and my non-imaginary numbers.

So, 4i-3+2i, 4i and 2i can be combined to be 6i. -3 doesn't have anything to join with so we end up with just -3. Really no different than anything else, just combining your like terms.

Please enter your name.

Are you sure you want to delete this comment?

###### Carl Horowitz

B.S. in Mathematics University of Michigan

He knows how to make difficult math concepts easy for everyone to understand. He speaks at a steady pace and his step-by-step explanations are easy to follow.

##### Sample Problems (2)

Need help with a problem?

Watch expert teachers solve similar problems.

## Comments (0)

Please Sign in or Sign up to add your comment.

## ·

Delete