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homad2000
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Complex numbers are numbers that have both a real part and an imaginary part. The real part is a normal number, while the imaginary part is a number multiplied by the imaginary unit, i, which is defined as the square root of -1. Complex numbers are usually written in the form a + bi, where a is the real part and bi is the imaginary part.
Complex numbers are used to solve problems that involve both real and imaginary quantities. They are especially useful in fields such as engineering, physics, and mathematics, where they can be used to model and solve various types of problems.
To add or subtract complex numbers, you simply add or subtract the real parts and the imaginary parts separately. For example, to add (3 + 2i) and (1 + 4i), you would add 3 and 1 to get 4 as the real part, and add 2i and 4i to get 6i as the imaginary part, resulting in the complex number 4 + 6i.
To multiply complex numbers, you use the FOIL method, just like you would with binomials. For example, to multiply (3 + 2i) and (1 + 4i), you would multiply each term in the first complex number by each term in the second complex number, resulting in the complex number -5 + 14i. To divide complex numbers, you use the conjugate of the denominator to eliminate the imaginary part in the denominator. For example, to divide (3 + 2i) by (1 + 4i), you would multiply the top and bottom by the conjugate of (1 + 4i), which is (1 - 4i), resulting in the complex number 11/17 + 2/17i.
No, complex numbers cannot be graphed on a number line because they have both a real and an imaginary part, making them two-dimensional. They are usually graphed on a complex plane, with the real part represented on the horizontal axis and the imaginary part represented on the vertical axis.