Simplifying Complex Expressions: A Step-by-Step Guide
This article will guide you through the process of simplifying the complex expression: (3-2i)(5+4i)-7i+1. We'll break down the steps, explaining the concepts involved.
Understanding Complex Numbers
Complex numbers are numbers that can be expressed in the form a + bi, where a and b are real numbers and i is the imaginary unit, defined as the square root of -1 (i² = -1).
Simplifying the Expression
-
Expanding the product:
-
Begin by multiplying the two complex numbers in the parentheses:
(3 - 2i)(5 + 4i) = 3(5 + 4i) - 2i(5 + 4i)
-
Apply the distributive property:
= 15 + 12i - 10i - 8i²
-
-
Substituting i²:
-
Replace i² with -1:
= 15 + 12i - 10i - 8(-1)
-
-
Combining real and imaginary terms:
-
Combine the real terms (15 and 8):
= 23 + 12i - 10i
-
Combine the imaginary terms (12i and -10i):
= 23 + 2i
-
-
Adding the remaining terms:
-
Add the remaining terms (-7i and 1) to the simplified result:
= 23 + 2i - 7i + 1
-
Combine the real and imaginary terms:
= 24 - 5i
-
Final Result
Therefore, the simplified form of the complex expression (3-2i)(5+4i)-7i+1 is 24 - 5i.