Numbers
Exam Prep Study Notes (Things to remember)
Rational numbers
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These are numbers that can be expressed as a fraction in the form of x/y, where x and y are integers, and y is not equal to zero. Rational numbers can be classified into subsets such as natural numbers, whole numbers and integers. |
Natural numbers
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Natural numbers are also known as counting numbers, namely {1, 2, 3, 4, ....} without the zero. Basically these are the positive integers. |
Integers
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All real numbers other than decimals or fractions are called as integers. Integers consist of all the whole numbers and their opposites. e.g. {....., -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, ......} |
Whole numbers
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All positive integers and includes 0. {0, 1, 2, 3, 4, ....} |
Exponent
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A number that denotes how many times that main number needs to be multiplied by itself |
Power
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The numerical value of the exponent |
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Tips
Adding integers
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If the signs are the same, Add and then keep the sign If the signs different, then Subtract and take the sign of the number with the larger absolute value |
Multiplying and dividing integers
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When multiplying or dividing integers, if you have an even number of negatives, the result will be positive. If you have an odd number of negatives, the result will be negative. |
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NUMBER BASE SYSTEMS
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Decimal(10)
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Binary(2)
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Hexadecimal(16)
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0 | 0 | 0 |
1 | 1 | 1 |
2 | 10 | 2 |
3 | 11 | 3 |
4 | 100 | 4 |
.... | ..... | .... |