All PSAT Math Resources
Example Questions
Example Question #121 : Exponents
If ax·a4 = a12 and (by)3 = b15, what is the value of x - y?
3
-9
6
-4
-2
3
Multiplying like bases means add the exponents, so x+4 = 12, or x = 8.
Raising a power to a power means multiply the exponents, so 3y = 15, or y = 5.
x - y = 8 - 5 = 3.
Example Question #1 : How To Find Patterns In Exponents
If p and q are positive integrers and 27p = 9q, then what is the value of q in terms of p?
(3/2)p
3p
(2/3)p
p
2p
(3/2)p
The first step is to express both sides of the equation with equal bases, in this case 3. The equation becomes 33p = 32q. So then 3p = 2q, and q = (3/2)p is our answer.
Example Question #123 : Exponents
Simplify 272/3.
9
729
3
27
125
9
272/3 is 27 squared and cube-rooted. We want to pick the easier operation first. Here that is the cube root. To see that, try both operations.
272/3 = (272)1/3 = 7291/3 OR
272/3 = (271/3)2 = 32
Obviously 32 is much easier. Either 32 or 7291/3 will give us the correct answer of 9, but with 32 it is readily apparent.
Example Question #124 : Exponents
If and are integers and
what is the value of ?
To solve this problem, we will have to take the log of both sides to bring down our exponents. By doing this, we will get .
To solve for we will have to divide both sides of our equation by to get .
will give you the answer of –3.
Example Question #125 : Exponents
If and , then what is ?
We use two properties of logarithms:
So
Example Question #1 : How To Find Patterns In Exponents
Evaluate:
, here and , hence .
Example Question #2 : How To Find Patterns In Exponents
Solve for
None of the above
=
which means
Example Question #571 : Algebra
Which of the following statements is the same as:
Remember the laws of exponents. In particular, when the base is nonzero:
An effective way to compare these statements, is to convert them all into exponents with base 2. The original statement becomes:
This is identical to statement I. Now consider statement II:
Therefore, statement II is not identical to the original statement. Finally, consider statement III:
which is also identical to the original statement. As a result, only I and III are the same as the original statement.
Example Question #3 : How To Find Patterns In Exponents
Write in exponential form:
Using properties of radicals e.g.,
we get
Example Question #1 : How To Find Patterns In Exponents
Write in exponential form:
Properties of Radicals