Unit 5 - Square and Cube Roots.

Summary of Knowledge.

When finished the unit you should know that to find the square root of a number, you want to find some number that when multiplied by itself, gives you the original number, the cube root of a number is some number that when multiplied by itself 3 times, gives you the original number.

Key Vocabulary.

Square Root: A divisor of a quantity that when squared gives the quantity. For example, the square roots of 25 are 5 and −5 because 5 × 5 = 25 and (−5) × (−5) = 25.

Cube Root:the number or quantity whose cube is a given number or quantity: 2 is the cube root of 8 (usually written 3square root 8 or 81/3).

Irrational Number: A number that cannot be expressed as a ratio between two integers and is not an imaginary number. If written in decimal notation, an irrational number would have an infinite number of digits to the right of the decimal point, without repetition.

Task Analysis.

Square Root

1. Have number of which you want to find square root.
2. Find the numbers square, a number that when multiplied by itself gives the initial number.
3. Plot number on problem.

Cubic Root

1. Have number of which you want to find cube root.
2. Find the numbers cube, a number that when multiplied by itself three times gives the initial number.
3. Plot number on problem.

Examples.
Square Root of 9 = 3, because 3 x 3 = 9.
Cube Root of 27 = 3, because 3 x 3 = 9 x 3 = 27, that equals 3 x 3 x 3.

Practice Quiz.

Square and cube roots » quiz builder

This Video Is So You Get It.

This video is just for fun so you hear good music untill you finish the exam.

This is for cube roots and how to get them.