Multiplying Complex Numbers: (-1 + 4i) * (4 - 3i)
This article will demonstrate how to multiply two complex numbers: (-1 + 4i) * (4 - 3i).
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 two complex numbers, we use the distributive property (or FOIL method) just like multiplying binomials in algebra.
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Distribute: Multiply each term in the first complex number by each term in the second complex number.
(-1 + 4i) * (4 - 3i) = (-1 * 4) + (-1 * -3i) + (4i * 4) + (4i * -3i)
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Simplify: Combine real and imaginary terms.
= -4 + 3i + 16i - 12i²
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Substitute i² = -1:
= -4 + 3i + 16i + 12
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Combine Like Terms:
= 8 + 19i
Result
Therefore, the product of (-1 + 4i) and (4 - 3i) is 8 + 19i.