Worksheets · Precalculus

Precalculus evaluating logarithms worksheet

A logarithm asks one question: what power of the base gives this number. The harder level uses fractions inside, which is where the negative answers come from.

Select your difficulty

Pick more than one for a sheet that mixes them.

Free math worksheets at sigmaprep.io/worksheets© 2026 Sigma Prep

Sigma Prep · sigmaprep.io/worksheets

Name

Evaluating Logarithms

Date Period

Evaluate each logarithm.

  1. log9(1729)
  2. log9(59049)
  3. log12(112)
  4. log9(729)
  5. log8(32768)
  6. log8(8)
  7. log7(1)
  8. log7(149)
  9. log8(1512)
  10. log8(512)
  11. log8(164)
  12. log9(6561)
  13. log9(9)
  14. log12(1144)
  15. log12(20736)
  16. log7(343)
  17. log7(17)
  18. log8(18)
  19. log9(181)
  20. log7(16807)

Free math worksheets at sigmaprep.io/worksheets© 2026 Sigma Prep

Sigma Prep · sigmaprep.io/worksheets

Name

Evaluating LogarithmsAnswer keyVersion 1

Date Period

Evaluate each logarithm.

  1. log9(1729)3
  2. log9(59049)5
  3. log12(112)1
  4. log9(729)3
  5. log8(32768)5
  6. log8(8)1
  7. log7(1)0
  8. log7(149)2
  9. log8(1512)3
  10. log8(512)3
  11. log8(164)2
  12. log9(6561)4
  13. log9(9)1
  14. log12(1144)2
  15. log12(20736)4
  16. log7(343)3
  17. log7(17)1
  18. log8(18)1
  19. log9(181)2
  20. log7(16807)5

Free math worksheets at sigmaprep.io/worksheets© 2026 Sigma Prep

How to do these

log2(8)

  1. The base is 2, so ask: 2 to what power is 8?
  2. 2³ = 8.

The answer is 3.

Where students go wrong

Reading it as division. log₂ 8 is not 4. Say the sentence out loud every time: two to the what gives eight.

Also called logarithms without a calculator or the meaning of a logarithm.

Questions about these worksheets

Yes. Every evaluating logarithms 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.

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.

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.

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.

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.

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 evaluating logarithms 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.

Yes. There are two 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.

Reading it as division. log₂ 8 is not 4. Say the sentence out loud every time: two to the what gives eight.