POWERS AND ROOTS
example, with 5 shirts and 7 pairs of pants to choose from, you can have 5 × 7 = 35 different
outfits.
43 . Probability
For example, if you have 12 shirts in a drawer and 9 of them are white, the probability of
picking a white shirt at random is This probability can also be expressed as 0.75 or
75%.
44 . Multiplying and Dividing Powers
To multiply powers with the same base, add the exponents and keep the same base:
x^3 × x^4 = x3+4 = x^7
To divide powers with the same base, subtract the exponents and keep the same base:
y^13 ÷ y^8 = y13−8 = y^5
45 . Raising Powers to Powers
To raise a power to a power, multiply the exponents:
(x^3 )^4 = x3×4 = x^12
46 . Simplifying Square Roots
To simplify a square root, factor out the perfect squares under the radical, unsquare them,
and put the result in front.
47 . Adding and Subtracting Roots