Survey

* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project

Survey

Document related concepts

Transcript

Number SQUARES AND SQUARE ROOTS OF NUMBERS Squares The square of a number is the number multiplied by itself. e.g. The square of 3 is 9, which is 3 x 3 The square of 10 is 100, which is 10 x 10 We can write a small 2 just above and to the right of a number to show that we want to square it. 32 102 So means ‘find the square of 3’ or ‘3 squared’ means ’10 squared’ A Now have a go at these. Work out: 1) 42 2) 62 3) 92 4) 12 5) 82 6) 122 7) 152 8) 202 9) 112 10) 252 We can square any number, not just whole numbers, in the same way. 1.22 = f lex i p e.g. 1.2 x 1.2 = 1.44 B. Try working these out. 1) 2.52 2) 3.62 3) 1.52 4) 2.82 5) 0.42 6) 0.62 7) 1.12 8) 0.32 9) 1.42 10) 5.52 ac k s 1 Number SQUARE ROOTS The square root of a number is the opposite of squaring a number. e.g. If the square of 3 is 9 ( which is 3 x 3) Then the square root of 9 is 3 We can use the sign to mean square root. So 9 means ‘the square root of 9’ To find the square root we have to think of a figure, multiplied by itself, that will give us the number. e.g. C. 1) 16 is 4, because 4 x 4 = 16 9 is 3, because 3 x 3 = 9 Now have a go at these. Write down the square roots of these numbers. 25 2) 100 3) 4 4) 36 5) 49 6) 81 7) 64 8) 1 It is not always straightforward to work out the square root of a number. Sometimes the number is very large, or the square root is not a whole number. f lex i p Most calculators have a square root sign button. It will have the square root sign on it. ac k s 2 Number D. Use a calculator to work out the square roots of the following. Ask a tutor if you are unsure how to use the square root button. 1) 256 2) 400 3) 900 4) 625 5) 1225 6) 169 7) 225 8) 289 9) 576 10) 961 E. Now have a go at these. Where you need to, write your answers to 3 decimal places. The first one is done for you. 1) 2 = 1.414 to 3 decimal places. 2) 1.44 3) 2.56 4) 9.61 5) 0.25 6) 5 7) 40 8) 20 9) 90 10) 1000 f lex i p Check your answers, then discuss with your tutor what you need to work on next. ac k s 3 Number Answers Square and Square Roots of Numbers A B C D f lex i p E 1) 16 2) 36 3) 81 4) 1 5) 64 6) 144 7) 225 8) 400 9) 121 10) 625 1) 6.25 2) 12.96 3) 2.25 4) 7.84 5) 0.16 6) 0.36 7) 1.21 8) 0.09 9) 1.96 10) 30.25 1) 5 2) 10 3) 2 4) 6 5) 7 6) 9 7) 8 8) 1 1) 16 2) 20 3) 30 4) 25 5) 35 6) 13 7) 15 8) 17 9) 24 10) 31 2) 1.2 3) 1.6 4) 3.1 5) 0.5 6) 2.236 7) 6.325 8) 4.472 9) 9.487 10) 31.623 ac k s 4