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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.

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Does Goblins support English Language Learners?

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AIII.F.33

Understand that restricting a trigonometric function to a domain on which it is always increasing or always decreasing allows its inverse to be constructed.

Example Problems

The following are all angle measures (in radians, rounded to the nearest hundredth) whose sine is

0.34

.
Which is the principal value of

\arcsin(0.34)

?

The following are all angle measures (in radians, rounded to the nearest hundredth) whose cosine is

-0.8

.
Which is the principal value of

\arccos(-0.8)

?

The following are all angle measures (in radians, rounded to the nearest hundredth) whose sine is

-0.66

.
Which is the principal value of

\arcsin(-0.66)

?

Khan Academy Resources

Evaluate inverse trig functions

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