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Example Questions
Example Question #4 : Fundamental Properties Of Roots & Exponents
can be expressed as:
It is important to be able to convert between root notation and exponent notation. The third root of a number (for example, is the same thing as taking that number to the one-third power
.
So when you see that you're taking the third root of , you can read that as
to the
power:
This then allows you to apply the rule that when you take one exponent to another power, you multiply the powers:
This then means that you can express this as:
Example Question #31 : Exponents & Roots
can be expressed as:
With roots, it is important that you are comfortable with factoring and with expressing roots as fractional exponents. A square root, for example, can be expressed as taking that base to the power. Using that rule, the given expression,
, could be expressed using fractional exponents as:
This would allow you to then add the exponents and arrive at:
Since that 2 in the denominator of the exponent translates to "square root," you would have the square root of :
If you were, instead, to work backward from the answer choices, you would see that answer choice factors to the given expression. If you start with:
You can express that as:
That in turn will factor to:
The first root then simplifies to , leaving you with:
Therefore, as you can see, choice factors directly back to the given expression.
Example Question #31 : Exponents & Roots
Which of the following is equal to for all positive values of
?
Simplify each of the expressions to determine which satisfies the condition of the problem:
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