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:
## Is pi a real number?

A: Pi is a real number, as all numbers that exist on a number line are real. Real numbers include all rational and irrational numbers; pi is defined as an irr... Full Answer >Filed Under: -
Q:
## What does "e" mean in math?

A: The number notated by "e" is a famous irrational number known as Euler's number that is approximately equal to 2.72. The number "e" has no final digit and ... Full Answer >Filed Under: -
Q:
## Is the number 2 prime?

A: The number 2 is a prime number. It is the smallest prime number and the only even number that is prime. Its only two factors are 1 and 2.... Full Answer >Filed Under: -
Q:
## How many zeros does the number 1 million have?

A: The number "one million" has six zeros after a one and before the decimal point. It is written out like this: "1,000,000." This is true in both the short-s... Full Answer >Filed Under: