2: Decimals Flashcards
Place value
Depends on its location within the number (Ex. Units, tens, hundreds, thousands)
10^0
1 (Ones)
10^-1
0.1 (Tenths)
How to multiply decimals
Count all the digits to the right of the decimal point - then multiply normally, ignoring the decimals. Put the same number of decimal places in the product.
Absolute Value
The POSITIVE value of the expression within the absolute value brackets. Inside the brackets can be positive or negative but the absolute value is always positive.
What are the three guessing strategies?
1) Identical twins (Both answers simplify to the same thing so either or is sufficient or neither are)
2) Cannibal (One statement completely incorporates the other)
3) C-Trap (Then don’t answer C or E)
0 Exponent (Raised to any power)
0 raised to any power equals 0
1 Exponent (Raised to any power)
1 raised to any power equals 1
(-1)^Odd
Any negative number to the power of an odd number will be a NEGATIVE number
(-1)^Even
Any negative number to the power of an even number will be a POSITIVE number
Base fraction negative (-) Exponent
If the base fraction is negative, then raising it to either an even or odd power makes the fraction LARGER
Raising to an even power turns the fraction positive (Positive fraction is larger than a negative one)
When raising negative base to an odd power it actually becomes less negative or closer to 0
What does a negative exponent mean?
General rule: Something with a negative exponent is just “one over” the same thing with a positive exponent.
How many solutions in x^2
2 - Positive and negative
How many solutions in the square root of x
1 - You can only square root a positive number therefore, x must be positive. Although if you take the square root of an equation with a squared variable than you would get positive and negative……
When to Test Cases
Data sufficiency (When the problem allows multiple possible values for the unknowns - Try to get different answers)
Problem solving (When the program asks a must be or could be question)