chap 2 rational # Flashcards
rational num and square roots
Rotational number
A number that can be expressed as a/b where the bottom number can no equal zero also known as a fraction ie: 1/2, 0.75, 2/1
Irrational number
A number that cannot be written as a fraction a decimal, they never end and never repeat ie: pi = 3.14159
descending order
big to small
Ascending order
small to big
equivalent fractions
fractions that have the same value even if they look different
ie: 1/2 = 3/6
Opposite rational numbers
Two num with the same num but different signs (+/-)
ie: 3 & -3
+ + =? (pos) (pos) =
- (neg)
+ - =? (pos) (neg) =
- (neg)
- =? (neg) (neg) =
+ (pos)
Adding and subtracting fractions
The fractions we + and - must have a common denominator (bottom number). Multiply the numerator and denominator of the fraction to create equivalent fractions. Add/subtract the numerator only (leave the denom the same) reduce fractions at end if possible
ie: 4/16 = 1/4
perfect square
a ration number that can be written as the produce of two identical numbers
ie: 64 = 8x8
Non-perfect square
A rational number that cannot be expressed as the product of 2 equal rational factions. Non repeating, non-terminating decimals and a approximate value can be found using a calculator
ie:65 = 8.062257748
Estimating squares
the square of a number can be calculated by using our knowledge of perfect squares
e: 2.6sqr2 is between 2 & 3 therefore is between 4 and 9
Estimating Square roots
the square root of a number can also be estimated by using our knowledge of perfect squares
ie: 18.7 is between perfect squares 16 & 25 so 18.7 is between 4 & 5
Can fractions b perfect square?
yea if the numerator and deominater are both perfect square then the fraction is also a perfect square
