A POWER is an expression that denotes a number multiplied by itself many times. This sounds complicated, but is really quite easy.
They are written like this:
32
There are two parts of a power, the BASE--
3
and the EXPONENT
2
A power signifies that the base is multiplied by itself the number of times in the exponent, so...
32 = 3 x 3
(you multiply 3 two times)
This equals 9
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25 = 2 x 2 x 2 x 2 x 2
(you multiply 2 five times)
This equals 32
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What is 42?
Powers have 3 important properties:
Product of Powers
When a power is multiplied to a power with the same base, the answer has the base raised to the power of the exponents added together.
am x an = a(m+n)
Here's why:
42 x 43
well, 42 = 4 x 4 and 43 = 4 x 4 x 4
put together, it's 4 x 4 x 4 x 4 x 4
or
45
[ 2 + 3 = 5 ]
Power of a Power
When a power is raised to a power, the answer has the base with the two powers multiplied together.
(am)n = a(mn)
Here's why:
(64)2
well, 64 = 6 x 6 x 6 x 6, and since they are squared, it can be represented by:
(6 x 6 x 6 x 6) x (6 x 6 x 6 x 6) OR 6 x 6 x 6 x 6 x 6 x 6 x 6 x 6
Simply
68
[ 4 x 2 = 8]
Power of a Product
When the base of a power has multiple terms multiplied together, the exponent gets distributed to all of the terms.
(ab)m = am x bm
Here's why:
(2Y)3
Well, (2Y)3 = (2 x 2 x 2) x (Y x Y x Y)
(23) x (Y3)
Without parentheses:
23 x Y3
Check out the videos and diagrams below to see these properties in action!
Learn how to use the Product of Powers property.
Learn how to use the Power of a Power property. Narrated by Rachel Kaplan.