Precalculus : Exponential and Logarithmic Functions

Study concepts, example questions & explanations for Precalculus

varsity tutors app store varsity tutors android store

Example Questions

Example Question #21 : Exponential And Logarithmic Functions

Find the inverse function of the following exponential function:

Possible Answers:

Correct answer:

Explanation:

Since we are looking for an inverse function, we start by swapping the x and y variables in our original equation.

Now we have to solve for y. To do this we have to work towards isolating y. First we remove the constant multiplier:

Next we eliminate the base on the right side by taking the natural log of both sides.

Subtract 1 and divide by 4:

Example Question #132 : Pre Calculus

Condense the following expression into one logarithm:

Possible Answers:

Correct answer:

Explanation:

To condense this, the second term must have the 2 in front moved inside.

When adding two logs, multiply their insides; when subtracting two logs, divide their insides.

Example Question #132 : Pre Calculus

Expand the following log completely

Possible Answers:

Correct answer:

Explanation:

To expand a logarithm, quantities in the inside that are multiplied get added and quantities in the inside that are divided get subtracted.

Example Question #12 : Properties Of Logarithms

Solve for :

Possible Answers:

Correct answer:

Explanation:

The first step to solving this problem is to realize that

Then, the equation falls into the follow form which resembles a quadratic.

Let . Then,

Thus, and .

Since ,

Example Question #22 : Exponential And Logarithmic Functions

Simplify the expression.

Possible Answers:

None of the above answers

Correct answer:

Explanation:

Using the quotient rule for logarithms we can condense these two logarithms into a single logarithm. 

 

We then obtain our answer by simple division.

Example Question #23 : Exponential And Logarithmic Functions

Simplify the expression.

Possible Answers:

Correct answer:

Explanation:

Using the properties of logarithms we first simplify the expression to .  Then we use the quotient rule for logarithms and cancel some terms to obtain our answer.

Example Question #15 : Properties Of Logarithms

Simplify the expression.

Possible Answers:

None of the other answers

Correct answer:

Explanation:

Using the properties of logarithms we first rewrite the expression as . Now we combine the three pieces into the form . We then obtain our answer when we combine the terms with and cancel those with .

Example Question #16 : Properties Of Logarithms

Solve for x:

Possible Answers:

Correct answer:

Explanation:

Example Question #139 : Pre Calculus

Which of the following is equivalent to  ?

Possible Answers:

Correct answer:

Explanation:

When multiplying exponents with a common base, you add both the exponents together. Hence, 

When an exponent is raised to an exponent you multiply the exponents together. Hence, for  you would multiply  to get .

Answer: 

Example Question #17 : Properties Of Logarithms

Solve the following for x:

Possible Answers:

Correct answer:

Explanation:

Learning Tools by Varsity Tutors