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 is the highest number?

A: There is no highest number. Higher numbers can always be formed by adding on to a previous number, a process that can go on infinitely. Infinity itself is ... Full Answer >Filed Under: -
Q:
## Is 2 a prime number?

A: Yes, 2 is a prime number. In fact, 2 is the only even number that is prime. A prime number is a number that has only two factors, the number 1 and itself. Full Answer >Filed Under: -
Q:
## What are the factors of the number 23?

A: The factors of the number 23 are 23 and 1. Factors of a number are the numbers that are multiplied together to equal the given number. Full Answer >Filed Under: -
Q:
## What are the factors of 4?

A: The factors of 4 are 4, 1 and 2. The product of two or more factors of a number is equal to that number. Four, 1 and 2 are factors because 1 x 4 = 4, 4 x 1... Full Answer >Filed Under: