All High School Math Resources
Example Questions
Example Question #41 : Pre Calculus
Indicate the first three terms of the following series:
In the arithmetic series, the first terms can be found by plugging , , and into the equation.
Example Question #2051 : High School Math
Indicate the first three terms of the following series:
In the arithmetic series, the first terms can be found by plugging in , , and for .
Example Question #3 : Finding Terms In A Series
Indicate the first three terms of the following series:
The first terms can be found by substituting , , and for into the sum formula.
Example Question #4 : Finding Terms In A Series
Indicate the first three terms of the following series.
Not enough information
The first terms can be found by substituting , , and in for .
Example Question #5 : Finding Terms In A Series
What is the sixth term when is expanded?
We will need to use the Binomial Theorem in order to solve this problem. Consider the expansion of , where n is an integer. The rth term of this expansion is given by the following formula:
,
where is a combination. In general, if x and y are nonnegative integers such that x > y, then the combination of x and y is defined as follows: .
We are asked to find the sixth term of , which means that in this case r = 6 and n = 10. Also, we will let and . We can now apply the Binomial Theorem to determine the sixth term, which is as follows:
Next, let's find the value of . According to the definition of a combination,
.
Remember that, if n is a positive integer, then . This is called a factorial.
Let's go back to simplifying .
The answer is .
Example Question #1 : Finding Partial Sums In A Series
Find the sum of all even integers from to .
The formula for the sum of an arithmetic series is
,
where is the number of terms in the series, is the first term, and is the last term.
We know that there are terms in the series. The first term is and the last term is . Our formula becomes:
Example Question #2 : Finding Partial Sums In A Series
Find the sum of all even integers from to .
The formula for the sum of an arithmetic series is
,
where is the number of terms in the series, is the first term, and is the last term.
Example Question #41 : Pre Calculus
Find the sum of the even integers from to .
The sum of even integers represents an arithmetic series.
The formula for the partial sum of an arithmetic series is
,
where is the first value in the series, is the number of terms, and is the difference between sequential terms.
Plugging in our values, we get:
Example Question #41 : Pre Calculus
Find the value for
To best understand, let's write out the series. So
We can see this is an infinite geometric series with each successive term being multiplied by .
A definition you may wish to remember is
where stands for the common ratio between the numbers, which in this case is or . So we get
Example Question #2 : Finding Sums Of Infinite Series
Evaluate:
The series does not converge.
This is a geometric series whose first term is and whose common ratio is . The sum of this series is: