1.5: Trigonometry Functions
- Page ID
- 2635
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When determining the designate angle we can use different ratios of sides.
- We can use a ratio of the opposite to the hypotenuse.
- We can use a ratio of the adjacent to the hypotenuse.
- We can use a ration of the opposite to the adjacent.
Each ratio has a trigonometric function that helps turn the ratio into an angle. They are:
- sin θ = opposite/hypotenuse
- cos θ = adjacent/hypotenuse
- tan θ = opposite/adjacent
One way of remembering the ratios are these mnemonics:
- SOH – Sine is opposite/ hypotenuse
- CAH – Cosine is adjacent/hypotenuse
- TOA – Tangent is opposite/ adjacent
By the way,
- sin is short for sine
- cos is short for cosine
- tan is short for tangent
Video!
This video walks through how to determine the angle of a right triangle when you have two sides.