Question 12
MediumOriginal questionA line makes angles , , with the coordinate axes. What is ?
Show the answer and explanation
CorrectNot quiteAnswer C
Correct answer: C
Explanation
, so the sum is .
.
Worth noting
1 is the sum of the squared cosines, not of the squared sines.
- Concept
- An identity for direction cosines
- Typical timeTypical
- 90 s
- Your timeYours
- —
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