Multiplying Complex Numbers: (6-8i)(9+2i)
This article will walk through the process of multiplying two complex numbers, (6-8i) and (9+2i).
Understanding Complex Numbers
Complex numbers are numbers of 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).
Multiplication Process
To multiply complex numbers, we use the distributive property, similar to multiplying binomials:
(6-8i)(9+2i) = 6(9) + 6(2i) - 8i(9) - 8i(2i)
Simplifying the Expression
Let's simplify the expression step by step:
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Multiply the terms:
- 6(9) = 54
- 6(2i) = 12i
- -8i(9) = -72i
- -8i(2i) = -16i²
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Substitute i² with -1:
- -16i² = -16(-1) = 16
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Combine like terms:
- 54 + 12i - 72i + 16 = 70 - 60i
Final Result
Therefore, the product of (6-8i) and (9+2i) is 70 - 60i.