# Precalculus Examples

, , , , ,

This is the formula to find the sum of the first terms of the sequence. To evaluate it, the values of the first and th terms must be found.

This is an arithmetic sequence since there is a common difference between each term. In this case, adding to the previous term in the sequence gives the next term. In other words, .

Arithmetic Sequence:

This is the formula of an arithmetic sequence.

Substitute in the values of and .

Apply the distributive property.

Rewrite as .

Multiply by to get .

Remove unnecessary parentheses.

Add and to get .

Add and to get .

Substitute in the value of to find the th term.

Multiply by to get .

Replace the variables with the known values to find .

Divide by to get .

Subtract from to get .

Multiply by to get .