Multiplying Complex Numbers: (2 + 3i)(1 - 4i)
This article will walk through the process of multiplying the complex numbers (2 + 3i) and (1 - 4i).
Understanding Complex Numbers
Before we begin, let's quickly recap what complex numbers are. A complex number is a number 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).
Multiplication Process
To multiply complex numbers, we use the distributive property, just like we would with any binomial multiplication.
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FOIL (First, Outer, Inner, Last):
- First: 2 * 1 = 2
- Outer: 2 * (-4i) = -8i
- Inner: 3i * 1 = 3i
- Last: 3i * (-4i) = -12i²
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Combine like terms:
- 2 - 8i + 3i - 12i²
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Substitute i² = -1:
- 2 - 8i + 3i - 12(-1)
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Simplify:
- 2 - 8i + 3i + 12
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Combine real and imaginary parts:
- (2 + 12) + (-8 + 3)i
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Final result:
- 14 - 5i
Conclusion
Therefore, the product of (2 + 3i) and (1 - 4i) is 14 - 5i.