Multiplying Complex Numbers: (5 + 3i)(2 - 5i)
This article will guide you through the process of multiplying two complex numbers: (5 + 3i) and (2 - 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 (i² = -1).
Multiplication Process
To multiply complex numbers, we use the distributive property, just like we do with binomials in algebra.
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Expand the expression: (5 + 3i)(2 - 5i) = 5(2 - 5i) + 3i(2 - 5i)
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Distribute: = 10 - 25i + 6i - 15i²
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Simplify using i² = -1: = 10 - 25i + 6i + 15
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Combine real and imaginary terms: = (10 + 15) + (-25 + 6)i
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Final Result: = 25 - 19i
Conclusion
Therefore, the product of the complex numbers (5 + 3i) and (2 - 5i) is 25 - 19i.