Imaginary Numbers

Question

How would you solve the expressions 2+3i and 2-3i where I is an imaginary number? (i=√-1)

Answer 1

Yasmine,

 

There is nothing to solve in your statement of the problem. No expression is stated. Two imaginary numbers are given.

 

But here is a couple of comments that might clarify your thinking.

 

The imaginary number (2 + 3i) can also be represented as (2 + 3√(-1)), but the "i form" is cleaner looking and requires less work to write or type it.

 

For students of Algebra, imaginary numbers arise as roots in solving some polynomial functions or using the quadratic formula whenever (B²-4AC) < 0 inside the square root.  They are much more extensively used in Electrical Engineering problems and some higher math subjects.

 

Again for us in Algebra, only their real part has physical meaning.  For example, if (2 + 3i) is a solution to a problem that asks how many buckets of water to add, then either you made a mistake in formulating or solving your problem (most likely), or if not, then just add 2 buckets of water and ignore the imaginary part, and hope that any bad effects will stay in the imaginary world :)