McGraw Hill Glencoe Algebra 1, 2012
MH
McGraw Hill Glencoe Algebra 1, 2012 View details
2. Real Numbers
Continue to next subchapter

Exercise 5 Page p10

Can you simplify the number?

Irrational number

Before we consider the given number, let's recall the various types of numbers.

  • Rational Number: A number is a rational number if it can be written in the form ab, where a and b are both integers and b≠ 0.
  • Integer: A number is an integer if it is a positive or negative counting number (or zero). All integers are also rational numbers because any number can be written as a division by one, a1.
  • Whole Number: A number is a whole number if it is a non-negative counting number. All whole numbers are also integers and rational numbers.
    • Natural Number: A number is a natural number if it is a positive counting number. All natural numbers are also whole numbers, integers, and rational numbers.
    • Irrational Number: An irrational number is a number that cannot be written in the form of a rational number. These are recognized as being non-repeating, infinite decimals.

    Now, let's try to categorize the given number using these definitions. -sqrt(22) Because none of the factors of the radicand are perfect squares, this square root cannot be simplified. We can, however, use a calculator to find its exact value. -sqrt(22)=- 4.690415... Because the decimal part is infinite with non-repeating digits, -sqrt(22) is an irrational number.