UNIT+3+Chapter+1+Number

__**Key aspects covered**__

1) Using calculator correctly (especially brackets, fractions, powers etc) 2) Reciprocals (including the appropriate calculator button) 3) Proving that a given recurring decimal can be written as a given fraction 4) Standard form and using your calculator properly


 * 1) Calculator modes and buttons**

If the exam asks you to work out the value of an expression on your calculator you should be able to enter it in EXACTLY the same form as the question asks, then press equals. You will probably have to use buttons such as fraction ( □ / □ ), power (x □ ), square root ( Ö ) and maybe other roots ( □ Ö ). Please make sure that you know where these buttons are and how to use them.

If your calculator does not have these buttons then you have two choices. You can either buy a calculator with the buttons (see Maths dept) or you can learn how to get the desired answer on your calculator. If you have any questions see me.


 * 2) Reciprocal**

The 'reciprocal' of a number //x// means '1 divided by that number //x//'. Your calculator should have a button that does this (x -1 ), although in the vast majority of cases you shouldn't need it! If the question is a bit nasty remember that it is far easier to work with a fraction (just flip it upside down to get its reciprocal) than a decimal (although your calculator should be able to cope regardless)


 * 3) Proving that a given recurring decimal can be written as a given fraction**

You did this for unit 2 - in unit 3 it is a little more formal. Always start with Let //x// = (the recurring decimal) Then multiply through by 10, and keep doing so until you have two decimals with the same 'recurring bit' that you can subtract. Always cancel down an the end (your calculator can do this for you!)


 * 4) Standard form and using your calculator properly**

You met standard form in unit 2. Any number can be written as (a number between 1 and 10 - can be 1 but not 10) multiplied by a power of 10. 'Big' numbers have positive powers of 10, 'small' numbers have a negative power of 10. Your calculator has a button for allowing you to enter numbers in standard form (EXP or x10// x )// You just have to know how to use it properly. Be warned - the question paper will nearly always ask you to give your answer in standard form - your calculator will not always do this for you, so you may have to work out how to write it. However - your calculator should be able to help you to check the answer.

Mr Gill is absent for both these lessons - we just work through all the questions from chapter 1 of the text book. PLEASE make sure you make a note of any questions you're not 100% sure about and ask on Wednesday (or asap)
 * Monday 25th June and Tuesday 26th June**