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Can I use my own voice with Goblins?

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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.

T.GT.2.b

Use the restrictions on the domain of an inverse trigonometric function to determine a value of the inverse trigonometric function.

Example Problems

The following are all angle measures, in degrees, whose cosine is

-1

.
Which is the principal value of

\arccos(-1)

?

The following are all angle measures, in degrees, whose tangent is

1

.
Which is the principal value of

\tan^{-1}(1)

?

The following are all angle measures, in degrees, whose cosine is

0.5

.
Which is the principal value of

\cos^{-1}(0.5)

?

Khan Academy Resources

Restrict domains of functions to make them invertible Restricting domains of functions to make them invertible Domain & range of inverse tangent function

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