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Does Goblins prevent cheating?

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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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HS.N.13(+).e

Compute the magnitude of a scalar multiple cv using ||cv||=|c|v. Compute the direction of cv knowing that when |c|v≠0, the direction of cv is either along v (for c>0) or against v (for c<0).

Example Problems

\vec{u} = (-9, 3)

Find the direction angle of

\vec{u}

.
Enter your answer as an angle in degrees between

0\degree

and

360\degree

rounded to the nearest hundredth.

\vec{u} = (6, 13)

Find the direction angle of

\vec{u}

.
Enter your answer as an angle in degrees between

0^\circ

and

360^\circ

rounded to the nearest hundredth.

\vec{u} = (6, -8)

Find the direction angle of

\vec{u}

.
Enter your answer as an angle in degrees between

0\degree

and

360\degree

rounded to the nearest hundredth.

Khan Academy Resources

Scalar multiplication

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