Multiplying Complex Numbers: A Step-by-Step Guide
This article will guide you through the process of multiplying the complex numbers (−4−5i) and (1−i).
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, where i² = -1.
The Multiplication Process
To multiply complex numbers, we use the distributive property, similar to multiplying binomials.
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Expand the product:
(-4 - 5i) * (1 - i) = (-4 * 1) + (-4 * -i) + (-5i * 1) + (-5i * -i)
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Simplify the terms:
= -4 + 4i - 5i + 5i²
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Substitute i² with -1:
= -4 + 4i - 5i + 5(-1)
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Combine real and imaginary terms:
= (-4 - 5) + (4 - 5)i
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Final Result:
= -9 - i
Conclusion
Therefore, the product of (-4 - 5i) and (1 - i) is -9 - i. By following these steps, you can confidently multiply any two complex numbers. Remember to always substitute i² with -1 to obtain a simplified result.