Write as a power series, and give the interval of convergence: f(x) = (1)/(1 - 5x)

of_n=0^infinity 5^n x^n, (-1/5, 1/5)

Write the first four nonzero terms of the Maclaurin series for cos (3x)

1 - 9/2x^2 + 27/8x^4 - 81/80x^6

Write as a power series, and give the interval of convergence: f(x) = (4)/(1 + 2x)

of_n=0^infinity 4(-2)^n x^n, (-1/2, 1/2)

Write as a power series, and give the interval of convergence: f(x) = -(6)/(1 + 2x)

of_n=0^infinity -6(-2)^n x^n, (-1/2, 1/2)

Write the first four nonzero terms of the Maclaurin series for sin (3x)

3x - 9/2x^3 + 81/40x^5 - 243/560x^7

Write as a power series, and give the interval of convergence: f(x) = -(5)/(1 - 5x)

of_n=0^infinity -5 × 5^n x^n, (-1/5, 1/5)

Write as a power series, and give the interval of convergence: f(x) = -(6)/(1 + 3x)

of_n=0^infinity -6(-3)^n x^n, (-1/3, 1/3)

Write the first four nonzero terms of the Maclaurin series for sin (2x)

2x - 4/3x^3 + 4/15x^5 - 8/315x^7

Write as a power series, and give the interval of convergence: f(x) = -(5)/(1 - 2x)

of_n=0^infinity -5 × 2^n x^n, (-1/2, 1/2)

Write as a power series, and give the interval of convergence: f(x) = (7)/(1 - 5x)

of_n=0^infinity 7 × 5^n x^n, (-1/5, 1/5)

Write as a power series, and give the interval of convergence: f(x) = (3)/(1 - 4x)

of_n=0^infinity 3 × 4^n x^n, (-1/4, 1/4)

Worksheets · Precalculus

Power series worksheet

Q: Are these power series worksheets free?

Yes. Every power series sheet is free to print and free to download as a PDF. There is no account to make, no email to hand over and no limit on how many you take.

Q: Do the power series worksheets come with an answer key?

Yes. The answer key prints on a second page, and you can choose whether it shows each question beside its answer or just the answers in a list.

Q: Are these power series worksheets printable?

Yes. Print straight from the page, or download the PDF and print that. The sheet is laid out for paper rather than squeezed off a screen, so there is room to work under each question, and the answer key comes out on its own page.

Q: What grade are these power series worksheets for?

Precalculus is usually taken around 11th or 12th grade, though schools vary and plenty of students meet it earlier or later. Pick the difficulty rather than the grade: the easy level suits a first lesson on it, the hard level suits review before a test.

Q: Can I get a different version of the same power series worksheet?

Yes, as many as you like. The questions are built fresh each time rather than picked from a fixed set of files, so pressing Generate gives a new sheet. That is what you want for a second class, a retake, or two students sitting next to each other.

Q: Is this a free alternative to Kuta Software for power series?

That is the closest comparison, and Kuta Software is good software. It is also paid software you install on a computer. These worksheets run in a browser tab for free, with no account and nothing to install. Like Kuta, the power series questions are generated when you ask for them rather than pulled from a fixed set of files, so two classes never get the same sheet, and the answer key comes with it.

Q: Can I choose how hard the power series questions are?

Yes. There are three levels, and you can tick more than one for a sheet that mixes them, in which case the questions come out easiest first. The harder levels are not just larger numbers: they ask for something the easy ones do not.

Q: What kinds of question are on a power series worksheet?

You pick from 3: a function as a power series, the interval of convergence and the first terms of a maclaurin series. Tick as many as you want and set how many of each, or let it spread them evenly.

Q: What do students get wrong with power series?

Stopping at the radius. The ratio test is inconclusive exactly at the endpoints, and each one can go either way: the same radius can give an open, closed or half-open interval.

A power series is an infinite polynomial. The geometric series 1/(1 - r) = 1 + r + r squared + ... is the one most others come from: put bx in place of r and it holds while |bx| < 1. For any power series the ratio test gives the radius, and the two endpoints have to be tested separately, because the ratio test says nothing there.

Select your difficulty

Pick more than one for a sheet that mixes them.



Sigma Prep · sigmaprep.io/worksheets Name Power Series Date Period Answer each question. Write as a power series, and give the interval of convergence: $f (x) = \frac{1}{1 - 5 x}$ Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x - 5)}^{n}}{3^{n}}$ Write the first four nonzero terms of the Maclaurin series for $\cos (3 x)$ Write as a power series, and give the interval of convergence: $f (x) = \frac{4}{1 + 2 x}$ Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 1)}^{n}}{3^{n}}$ Write the first four nonzero terms of the Maclaurin series for $e^{- 2 x}$ Write as a power series, and give the interval of convergence: $f (x) = - \frac{6}{1 + 2 x}$ Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 5)}^{n}}{4^{n}}$ Write the first four nonzero terms of the Maclaurin series for $\sin (3 x)$ Write as a power series, and give the interval of convergence: $f (x) = - \frac{5}{1 - 5 x}$ Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 3)}^{n}}{5^{n}}$ Write the first four nonzero terms of the Maclaurin series for $\ln (1 - 3 x)$ Write as a power series, and give the interval of convergence: $f (x) = - \frac{6}{1 + 3 x}$ Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 4)}^{n}}{5^{n}}$ Write the first four nonzero terms of the Maclaurin series for $\sin (2 x)$ Write as a power series, and give the interval of convergence: $f (x) = - \frac{5}{1 - 2 x}$ Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x - 5)}^{n}}{5^{n}}$ Write the first four nonzero terms of the Maclaurin series for $\frac{1}{1 + 2 x}$ Write as a power series, and give the interval of convergence: $f (x) = \frac{7}{1 - 5 x}$ Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x - 4)}^{n}}{6^{n}}$ Free math worksheets at sigmaprep.io/worksheets© 2026 Sigma Prep

Sigma Prep · sigmaprep.io/worksheets

Name

Power Series

Date Period

Answer each question.

Write as a power series, and give the interval of convergence: $f (x) = \frac{1}{1 - 5 x}$
Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x - 5)}^{n}}{3^{n}}$
Write the first four nonzero terms of the Maclaurin series for $\cos (3 x)$
Write as a power series, and give the interval of convergence: $f (x) = \frac{4}{1 + 2 x}$
Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 1)}^{n}}{3^{n}}$
Write the first four nonzero terms of the Maclaurin series for $e^{- 2 x}$
Write as a power series, and give the interval of convergence: $f (x) = - \frac{6}{1 + 2 x}$
Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 5)}^{n}}{4^{n}}$
Write the first four nonzero terms of the Maclaurin series for $\sin (3 x)$
Write as a power series, and give the interval of convergence: $f (x) = - \frac{5}{1 - 5 x}$
Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 3)}^{n}}{5^{n}}$
Write the first four nonzero terms of the Maclaurin series for $\ln (1 - 3 x)$
Write as a power series, and give the interval of convergence: $f (x) = - \frac{6}{1 + 3 x}$
Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 4)}^{n}}{5^{n}}$
Write the first four nonzero terms of the Maclaurin series for $\sin (2 x)$
Write as a power series, and give the interval of convergence: $f (x) = - \frac{5}{1 - 2 x}$
Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x - 5)}^{n}}{5^{n}}$
Write the first four nonzero terms of the Maclaurin series for $\frac{1}{1 + 2 x}$
Write as a power series, and give the interval of convergence: $f (x) = \frac{7}{1 - 5 x}$
Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x - 4)}^{n}}{6^{n}}$



Sigma Prep · sigmaprep.io/worksheets Name Power SeriesAnswer keyVersion 1 Date Period Answer each question. Write as a power series, and give the interval of convergence: $f (x) = \frac{1}{1 - 5 x}$ $\sum_{n = 0}^{\infty} 5^{n} x^{n}$ , $(- \frac{1}{5}, \frac{1}{5})$ Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x - 5)}^{n}}{3^{n}}$ $(2, 8)$ Write the first four nonzero terms of the Maclaurin series for $\cos (3 x)$ $1 - \frac{9}{2} x^{2} + \frac{27}{8} x^{4} - \frac{81}{80} x^{6}$ Write as a power series, and give the interval of convergence: $f (x) = \frac{4}{1 + 2 x}$ $\sum_{n = 0}^{\infty} 4 {(- 2)}^{n} x^{n}$ , $(- \frac{1}{2}, \frac{1}{2})$ Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 1)}^{n}}{3^{n}}$ $(- 4, 2)$ Write the first four nonzero terms of the Maclaurin series for $e^{- 2 x}$ $1 - 2 x + 2 x^{2} - \frac{4}{3} x^{3}$ Write as a power series, and give the interval of convergence: $f (x) = - \frac{6}{1 + 2 x}$ $\sum_{n = 0}^{\infty} - 6 {(- 2)}^{n} x^{n}$ , $(- \frac{1}{2}, \frac{1}{2})$ Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 5)}^{n}}{4^{n}}$ $(- 9, - 1)$ Write the first four nonzero terms of the Maclaurin series for $\sin (3 x)$ $3 x - \frac{9}{2} x^{3} + \frac{81}{40} x^{5} - \frac{243}{560} x^{7}$ Write as a power series, and give the interval of convergence: $f (x) = - \frac{5}{1 - 5 x}$ $\sum_{n = 0}^{\infty} - 5 \cdot 5^{n} x^{n}$ , $(- \frac{1}{5}, \frac{1}{5})$ Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 3)}^{n}}{5^{n}}$ $(- 8, 2)$ Write the first four nonzero terms of the Maclaurin series for $\ln (1 - 3 x)$ $- 3 x - \frac{9}{2} x^{2} - 9 x^{3} - \frac{81}{4} x^{4}$ Write as a power series, and give the interval of convergence: $f (x) = - \frac{6}{1 + 3 x}$ $\sum_{n = 0}^{\infty} - 6 {(- 3)}^{n} x^{n}$ , $(- \frac{1}{3}, \frac{1}{3})$ Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 4)}^{n}}{5^{n}}$ $(- 9, 1)$ Write the first four nonzero terms of the Maclaurin series for $\sin (2 x)$ $2 x - \frac{4}{3} x^{3} + \frac{4}{15} x^{5} - \frac{8}{315} x^{7}$ Write as a power series, and give the interval of convergence: $f (x) = - \frac{5}{1 - 2 x}$ $\sum_{n = 0}^{\infty} - 5 \cdot 2^{n} x^{n}$ , $(- \frac{1}{2}, \frac{1}{2})$ Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x - 5)}^{n}}{5^{n}}$ $(0, 10)$ Write the first four nonzero terms of the Maclaurin series for $\frac{1}{1 + 2 x}$ $1 - 2 x + 4 x^{2} - 8 x^{3}$ Write as a power series, and give the interval of convergence: $f (x) = \frac{7}{1 - 5 x}$ $\sum_{n = 0}^{\infty} 7 \cdot 5^{n} x^{n}$ , $(- \frac{1}{5}, \frac{1}{5})$ Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x - 4)}^{n}}{6^{n}}$ $(- 2, 10)$ Free math worksheets at sigmaprep.io/worksheets© 2026 Sigma Prep

Sigma Prep · sigmaprep.io/worksheets

Name

Power SeriesAnswer keyVersion 1

Date Period

Answer each question.

Write as a power series, and give the interval of convergence: $f (x) = \frac{1}{1 - 5 x}$ $\sum_{n = 0}^{\infty} 5^{n} x^{n}$ , $(- \frac{1}{5}, \frac{1}{5})$
Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x - 5)}^{n}}{3^{n}}$ $(2, 8)$
Write the first four nonzero terms of the Maclaurin series for $\cos (3 x)$ $1 - \frac{9}{2} x^{2} + \frac{27}{8} x^{4} - \frac{81}{80} x^{6}$
Write as a power series, and give the interval of convergence: $f (x) = \frac{4}{1 + 2 x}$ $\sum_{n = 0}^{\infty} 4 {(- 2)}^{n} x^{n}$ , $(- \frac{1}{2}, \frac{1}{2})$
Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 1)}^{n}}{3^{n}}$ $(- 4, 2)$
Write the first four nonzero terms of the Maclaurin series for $e^{- 2 x}$ $1 - 2 x + 2 x^{2} - \frac{4}{3} x^{3}$
Write as a power series, and give the interval of convergence: $f (x) = - \frac{6}{1 + 2 x}$ $\sum_{n = 0}^{\infty} - 6 {(- 2)}^{n} x^{n}$ , $(- \frac{1}{2}, \frac{1}{2})$
Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 5)}^{n}}{4^{n}}$ $(- 9, - 1)$
Write the first four nonzero terms of the Maclaurin series for $\sin (3 x)$ $3 x - \frac{9}{2} x^{3} + \frac{81}{40} x^{5} - \frac{243}{560} x^{7}$
Write as a power series, and give the interval of convergence: $f (x) = - \frac{5}{1 - 5 x}$ $\sum_{n = 0}^{\infty} - 5 \cdot 5^{n} x^{n}$ , $(- \frac{1}{5}, \frac{1}{5})$
Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 3)}^{n}}{5^{n}}$ $(- 8, 2)$
Write the first four nonzero terms of the Maclaurin series for $\ln (1 - 3 x)$ $- 3 x - \frac{9}{2} x^{2} - 9 x^{3} - \frac{81}{4} x^{4}$
Write as a power series, and give the interval of convergence: $f (x) = - \frac{6}{1 + 3 x}$ $\sum_{n = 0}^{\infty} - 6 {(- 3)}^{n} x^{n}$ , $(- \frac{1}{3}, \frac{1}{3})$
Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x + 4)}^{n}}{5^{n}}$ $(- 9, 1)$
Write the first four nonzero terms of the Maclaurin series for $\sin (2 x)$ $2 x - \frac{4}{3} x^{3} + \frac{4}{15} x^{5} - \frac{8}{315} x^{7}$
Write as a power series, and give the interval of convergence: $f (x) = - \frac{5}{1 - 2 x}$ $\sum_{n = 0}^{\infty} - 5 \cdot 2^{n} x^{n}$ , $(- \frac{1}{2}, \frac{1}{2})$
Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x - 5)}^{n}}{5^{n}}$ $(0, 10)$
Write the first four nonzero terms of the Maclaurin series for $\frac{1}{1 + 2 x}$ $1 - 2 x + 4 x^{2} - 8 x^{3}$
Write as a power series, and give the interval of convergence: $f (x) = \frac{7}{1 - 5 x}$ $\sum_{n = 0}^{\infty} 7 \cdot 5^{n} x^{n}$ , $(- \frac{1}{5}, \frac{1}{5})$
Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{{(x - 4)}^{n}}{6^{n}}$ $(- 2, 10)$

How to do these

Interval of convergence: $\sum_{n = 1}^{\infty} \frac{x^{n}}{n \cdot 3^{n}}$

Ratio test: the ratio of consecutive terms tends to |x|/3, so the series converges for |x| < 3.
At x = 3 it is the sum of 1/n, which diverges.
At x = -3 it is the alternating sum of 1/n, which converges.

The answer is $[- 3, 3)$ .

Where students go wrong

Stopping at the radius. The ratio test is inconclusive exactly at the endpoints, and each one can go either way: the same radius can give an open, closed or half-open interval.

Also called power series, interval of convergence, radius of convergence, Maclaurin series or representing functions as power series.

What you can put on this worksheet

A function as a power series: Write as a power series, and give the interval of convergence: $f (x) = \frac{3}{1 - 4 x}$ → $\sum_{n = 0}^{\infty} 3 \cdot 4^{n} x^{n}$ , $(- \frac{1}{4}, \frac{1}{4})$
The interval of convergence: Find the interval of convergence: $\sum_{n = 0}^{\infty} \frac{x^{n}}{6^{n}}$ → $(- 6, 6)$
The first terms of a Maclaurin series: Write the first four nonzero terms of the Maclaurin series for $\cos (2 x)$ → $1 - 2 x^{2} + \frac{2}{3} x^{4} - \frac{4}{45} x^{6}$

Questions about these worksheets