Multiplying Complex Numbers: (−2+2i)⋅(5+5i)
This article will guide you through the process of multiplying two complex numbers, specifically: (−2+2i)⋅(5+5i).
Understanding Complex Numbers
Before we delve into the multiplication, let's refresh our understanding of 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 follow a similar approach to multiplying binomials:
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Expand using the distributive property (FOIL method):
(-2 + 2i)(5 + 5i) = (-2 * 5) + (-2 * 5i) + (2i * 5) + (2i * 5i)
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Simplify the terms:
= -10 - 10i + 10i + 10i²
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Substitute i² with -1:
= -10 - 10i + 10i - 10
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Combine real and imaginary terms:
= (-10 - 10) + (-10 + 10)i
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Final result:
= -20
Conclusion
Therefore, the product of (−2+2i)⋅(5+5i) is -20. It's important to note that the result is a real number, even though we started with two complex numbers.