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Yes. Goblins offers a generous free tier that includes 1 live feedback assignment per week, insights on student mastery and replays, and the ability to upload your own content. The Max plan adds unlimited assignments, superadaptive mode, grade exports, standards growth reports, and SSO/LMS integration, with per-student pricing for schools and districts.

How does Goblins work?

Three simple steps: (1) Share an assignment from thousands of standards-aligned topics using a share code. (2) Students speak and draw their thinking naturally, and Goblins responds with Socratic questioning that sounds just like their teacher. (3) Teachers get real-time formative insights showing what students struggle with and suggestions to inform instruction.

Does Goblins prevent cheating?

Yes. Goblins uses a purpose-trained AI model that evaluates cheating signals in real time. It can detect when students are copying answers, using external tools inappropriately, or not genuinely working through problems. Copy-pasting answers is also blocked.

Can I use my own voice with Goblins?

Yes. Teachers can record their voice and take a selfie to create a custom 3D avatar in about 30 seconds. Students then hear help in their own teacher's voice and see a familiar face, making the experience more personal and effective.

What math levels does Goblins cover?

Goblins covers math from Grade 5 through AP Calculus, including thousands of standards-aligned topics. Teachers can also upload their own content for custom assignments at any level.

Is Goblins FERPA compliant?

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Does Goblins support English Language Learners?

Yes. Goblins supports 30+ languages so teachers don't have to translate every worksheet. It is especially helpful for ELL students who need accessible math instruction in their native language.

What grade level is PC.FBF.5 taught?

This standard is part of the PC curriculum in South Carolina College- and Career-Ready Standards - Mathematics.

Are there practice problems for PC.FBF.5?

Yes, there are 3 practice problems available for PC.FBF.5 with worked examples.

What learning resources are available for PC.FBF.5?

There are 30 Khan Academy resources available for PC.FBF.5, including 20 videos, 7 exercises, 3 articles.

PC.FBF.5: Understand and verify through function composition that exponential and logarithmic functions are inverses of each other and use this relati... | SC CCR

Understand and verify through function composition that exponential and logarithmic functions are inverses of each other and use this relationship to solve problems involving logarithms and exponents.

Example Problems

Evaluate:

\log_4(4)

Evaluate:

\log_9(1)

Evaluate:

\log_8(8)

Khan Academy Resources

Intro to logarithm properties Intro to Logarithms Justifying the logarithm properties Evaluate logarithms (advanced)Evaluate logarithms Use the properties of logarithms Relationship between exponentials & logarithms Exponential vs. linear models Exponential expressions word problems (numerical)Exponential vs. linear growth over time Intro to logarithms Evaluating logarithms (advanced)Proof of the logarithm product rule Proof of the logarithm quotient and power rules Intro to exponential functions Intro to logarithm properties (1 of 2)Intro to logarithm properties (2 of 2)Using the logarithmic product rule Using the properties of logarithms: multiple steps Using the logarithmic power rule Relationship between exponentials & logarithms: graphs Relationship between exponentials & logarithms Exponential expressions word problems (numerical)Initial value & common ratio of exponential functions Exponential vs. linear models: verbal Relationship between exponentials & logarithms: tables Graphical relationship between 2ˣ and log₂(x)Analyzing graphs of exponential functions Modeling with basic exponential functions word problem Analyzing graphs of exponential functions: negative initial value

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PC.FBF.5: Understand and verify through function composition that exponential and logarithmic functions are inverses of each other and use this relationship to solve problems involving logarithms and exponents.