Combine the set of rational numbers and the set of irrational number.
Real numbers
Square root of a negative number.
Imaginary numbers
i
Imaginary unit
Rule 1: If the number is positive, the absolute value of the number is itself.
Rule 2: If the number is negative, drop the negative sign.
Absolute value of a number is its distance from zero.
Addition of Integers (Same sign)
Add and keep the sign.
Addition of Integers (Diff sign)
Subtract and take sign of larger value.
Subtraction of Integers
Change operation into addition and reverse sign of the second integer.
Multiplication and Division of Integers
Same sign is positive answer. Diff signs is negative answer.
First, perform the operation inside the parenthesis or grouping symbol.
Simplify any number with exponents.
Perform multiplication or division from left to right.
Perform addition or subtraction from left to right.
PEMDAS
The numbers we multiply to obtain another number (or the product).
Factors
Whole number greater than one with only two factors: 1 and itself.
Prime number
Whole number that has more than two factors.
Composite number
Process of expressing a composite number as a product of its prime factors.(Factor tree)
Prime Factorization
Result when we multiply a number by an integer.
Multiple
What is the smallest even number that is also a prime number?
2
Can be divided by the latter and leaves no remainder.
Divisible
Integer is divisible by two if its last digit is ____.
Even
Integer is divisible by four if?
If the last two digits are divisible by 4.
Integer is divisible by three if?
If the sum of it's digits is divisible by 3.
Integer is divisible by two if?
if the last digit is even (0, 2, 4, 6, and 8).
Integer is divisible by five if?
If the last digit is 0 or 5.
Integer is divisible by six if?
If it is even and divisible by 3.
Integer is divisible by seven if?
Double the last digit of the integer. (294 is 4; 4 × 2 = 8)
Subtract the number you obtained in Step 1 from the number made by the other digits. (29 – 8 = 21)
If the resulting number is divisible by 7.
Integer is divisible by eight if?
If its last three digits are divisible by 8.
Integer is divisible by nine if?
If the sum of its digits is divisible by 9.
Which numbers are divisible by 0?
Any number divided by 0 is undefined. Meanwhile, if you divide 0 by itself or 0 divided by 0 is indeterminate.
25% is equivalent to 25⁄100 or ¼. Hence, to find the 25% of a number, divide the given number by 4.
50% is equivalent to 50⁄100 or ½. Thus, to find the 50% of a number, divide the given number by 2. This means 50% of a number is just half the given number.
75% is equivalent to 75⁄100 or ¾. Thus, to find the 75% of a number, multiply the given number by three and then divide the result by 4.