Sine, Cosine, and Tangent Ratios
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Objective
I can define sine, cosine, and tangent in terms of right triangle ratios.
Part 1 of 4
Warm-up video
Professor Dave Explains · 7:18Vetted channel
We don't generate video — this one is by Professor Dave Explains on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.
Part 2 of 4
Key concepts
3 concepts
- 1
For a right triangle, the sine of an angle is the ratio of the opposite side to the hypotenuse.
- 2
SOHCAHTOA is a mnemonic device that helps us remember that sine is opposite over hypotenuse, cosine is adjacent over hypotenuse, and tangent is opposite over adjacent.
- 3
The cosecant, secant, and cotangent functions are the reciprocals of the sine, cosine, and tangent functions, respectively.
Part 3 of 4
Practice
6 questions
Define the sine of an angle θ in a right triangle in terms of its sides.
What is the mnemonic used to remember the definitions of sine, cosine, and tangent?
Part 4 of 4
Exit ticket
Quick comprehension check
“In a right triangle, the side opposite angle θ has a length of 8, and the hypotenuse has a length of 17. What is sin(θ)?”
Sample answer included in the free materials
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