Math review Flashcards
Product of integers:
Even * Even =
Odd * Odd =
Even * Odd =
Even * Even = Even (2*2=4)
Odd * Odd = Odd (1*1=1)
Even * Odd = Even (2*1=2)
Multiple
A multiple is divisible by each of its divisors/factors “25 is a multiple of: 1,5,25, and their negatives.”
Sum of integers:
Even + Even =
Odd + Odd =
Even + Odd =
Even + Even = Even (2+2=4)
Odd + Odd = Even (1+1=2)
Even + Odd = Odd (2+1=3)
Prime number
- x>1 and
- Only 2 positive factors, 1 and x
i. e. 2,3,5,7,11,13,17,19,23,29
1 is not prime number.
2 is only prime number that is even.
Composite number
- x>1 and
- Not prime number
i. e., 4,6,8,9,10,12,14,15,18,20,21
Rational number
Any number that can be made by dividing one integer by another. The word comes from “ratio”. Examples: 1/2 is a rational number (1 divided by 2, or the ratio of 1 to 2)
Mixed number
A number that is the sum of a whole number and a proper fraction is called a mixed number. i.e. 4 3/8 = (4/1)+(3/8) = ((4*8)+3)/8 = 35/8
Exponent basics
(-) Number ^ even number = (+)
(-) Number ^ odd number = (-)
-3^2= -9
a^0 = 1 (a ≠ 0)
0^0=undefined
(a)(a^-1)=1
(a ≥ 0, m ≥ 0, n > 0)
Careful!!
- (a + b)^n ≠ a^n + b^n
- (a – b)^n ≠ a^n – b^n
Square root Basics
Cube root and n-th root
For ODD-order roots, there is exactly 1 root for every number a (i.e. cubed root).
- cubed root of 8 = cubed root of 8
- cubed root of -8 = cubed root of -8
If n is odd then .
For even-order roots, there are exactly 2 roots for every positive number a and NO root for any negative number a (i.e. fourth root).
fourth root of 8 = (+) and (-) fourth root of 8
fourth root of -8 = NONE
If n is even then .
Distributing (a ≥ 0 and b ≥ 0)
Careful!
Rational number
can be expressed as a TERMINATING or REPEATING decimal
however, not every decimal is terminating or repeating (i.e. Square root of 2 = 1.4142135… = IRRATIONAL number)
Real number
Rational number (integer, fraction, decimal) + Irrational number
Triangle Inequality
Geometrically, the right-hand part of the triangle inequality states that the sum of the lengths of any two sides of a triangle is greater than the length of the remaining side.