Simplifying Complex Expressions
This article will explore the simplification of the complex expression: (4 + 3zi)(6 + 5i) - (4 + i)(6 + 5i)
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 (i.e., i² = -1).
Simplifying the Expression
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Expand the products:
We begin by expanding the products using the distributive property (FOIL method):
(4 + 3zi)(6 + 5i) = (4 * 6) + (4 * 5i) + (3zi * 6) + (3zi * 5i) = 24 + 20i + 18zi + 15zi²
(4 + i)(6 + 5i) = (4 * 6) + (4 * 5i) + (i * 6) + (i * 5i) = 24 + 20i + 6i + 5i²
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Simplify using i² = -1:
We substitute i² with -1 in both expanded products:
24 + 20i + 18zi + 15zi² = 24 + 20i + 18zi - 15z 24 + 20i + 6i + 5i² = 24 + 20i + 6i - 5
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Combine like terms:
Now we combine the real and imaginary terms separately:
(24 - 15z) + (20 + 18z)i - (24 - 5) - (20 + 6)i
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Simplify further:
Simplifying the expression:
(-15z + 5) + (18z - 14)i
Final Result
The simplified form of the expression (4 + 3zi)(6 + 5i) - (4 + i)(6 + 5i) is (-15z + 5) + (18z - 14)i.
This demonstrates a common method for simplifying complex expressions involving multiplication and subtraction. By applying the properties of complex numbers and algebraic manipulation, we can arrive at a simplified form that is easier to understand and work with.