Q:
# What is a non-real number?

**A non-real, or imaginary, number is any number that, when multiplied by itself, produces a negative number.** Mathematicians use the letter "i" to symbolize the square root of -1. An imaginary number is any real number multiplied by i. For example, 5i is imaginary; the square of 5i is -25.

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No real negative number can have a negative square root, because even a negative number multiplied by itself produces a positive product. Real numbers are those numbers that represent a quantity along a number line, including all positive and negative numbers and zero. Irrational numbers, even though they cannot be expressed as a precise fraction or decimal, are considered real numbers because they do exist at some place on the number line, even if that place is not precisely defined.

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Q:
## What are the factors of 11?

A: The number 11 only has two factors, which are 1 and 11. The number 11 is an example of a prime number, which is any number that only has two factors, 1 and... Full Answer >Filed Under: -
Q:
## What is the reciprocal of a negative number?

A: The reciprocal of a negative number is also a negative number because when the two numbers are multiplied the answer is 1. For example, the reciprocal of -... Full Answer >Filed Under: -
Q:
## What are the multiples of six?

A: There is an infinite number of multiples of six. A multiple of six is any number that is divisible by six, such as 12, 24, 360 or 7,907,560,848 Full Answer >Filed Under: -
Q:
## What is a prime number in math?

A: A prime number in math is an integer greater than 1 that is evenly divisible by only 1 and the number itself. One is not considered a prime number, because... Full Answer >Filed Under: