MTH 3-06a 10-Jan-16Compiled by Mr. Lafferty Maths Dept. Powers & Roots Squares, Cubes and Powers (Indices) Square Roots and Cube Roots

MTH 3-06a 10-Jan-16Compiled by Mr. Lafferty Maths Dept. Starter Questions

MTH 3-06a 10-Jan-16Compiled by Mr. Lafferty Maths Dept. Squaring a Number Learning Intention Success Criteria 1.To understand what is meant by the term power of a number. 1.We are learning the term about powers of a number’. about powers of a number’. 2.Be able to calculate powers of a number squares both mentally and using the calculator.

MTH 3-06a 10-Jan-16Compiled by Mr. Lafferty Maths Dept. Square of a Number To square a number means to : “Multiply it by itself” means 9 x 9 = 81 Example : means 10 x 10 =

MTH 3-06a 10-Jan-16Compiled by Mr. Lafferty Maths Dept. Cube of a Number To cube a number means to : “Multiply it by itself and then itself again” means 2 x 2 x 2 = 8 Example : means 4 x 4 x 4 =

MTH 3-06a 10-Jan-16Compiled by Mr. Lafferty Maths Dept. Index of a Number means 2 x 2 x 2 x 2 x 2 = anan n is called the index number a is called the base number Example :

10-Jan-16Mr NON - CALCULATOR

MTH 3-06a 10-Jan-16Compiled by Mr. Lafferty Maths Dept. Area of Square = 7 2 = 49cm 2 Example :Find the area of a square with length 7cm. Area of a square is A = l x l = l 2 A = l 2 l cm

10-Jan-16 Compiled by Mr. Lafferty Maths Dept. Special button on the calculator

MTH 3-06a 10-Jan-16Created by Mr. Lafferty Maths Dept. Now try TJ3b Ex 1 Ch1 (page 8) Powers & Roots

MTH 3-06a 10-Jan-16Compiled by Mr. Lafferty Maths Dept. Square Root of a Number You now know how to find : We can ‘undo’ this by asking “which number, times itself, gives 81” 9 2 = 9 x 9 = 81 From the top line, the answer is 9 This is expressed as : “ ““ “the SQUARE ROOT of 81 is 9” or in symbols we write :

MTH 3-06a 10-Jan-16Compiled by Mr. Lafferty Maths Dept. Cube Root of a Number You now know how to find : We can ‘undo’ this by asking “which number, times itself, times itself again gives 8” 2 3 = 2 x 2 x 2 = 8 From the top line, the answer is 2 This is expressed as : “the CUBE ROOT of 8 is 2” or in symbols we write :

MTH 3-06a 10-Jan-16Compiled by Mr. Lafferty Maths Dept. Roots of a Number means 4 x 4 = 16 Example : 4 2 so √16 = 4 means 5 x 5 x 5 = so 3 √125 = 5

10-Jan-16Mr NON - CALCULATOR

MTH 3-06a 10-Jan-16Compiled by Mr. Lafferty Maths Dept. Length of a Square = √400 Example :Find the length of the square. Area of a square is A = l x l = l 2 l = √A l cm 400cm 2 l = 20 cm

10-Jan-16 Compiled by Mr. Lafferty Maths Dept. Special button on the calculator

MTH 3-06a 10-Jan-16Created by Mr. Lafferty Maths Dept. Now try TJ3b Ex 2 Ch1 (page 10) Powers & Roots Have you updated your Learning Log ?