- A dilation on the y−value of a trigonometric function. A is multiplied by the function, to make it stretch or shorten.
- Angular Velocity
- The velocity of rotation, measured in radians.
- Arc Length
- The length of a portion of the circumference of a circle. The formula is θ⋅2πr, where θ is the corresponding central angle, in radians.
- Circular Function
- The collective term for a function that can be defined by the unit circle.
- Critical Angle(s)
- Any angle that is a multiple of 30∘ or 45∘.
- A transformation that changes the size of an object or function.
- The number of times the graph repeats in 2π or π for tangent and cotangent.
- The distance it takes a graph to complete one phase.
- Phase Shift
- The shift, or translation, in the x−direction of a trigonometric function. Also called a horizontal translation.
- An alternate way to measure degrees, defined by the arc length on a circle that is equal to the radius. 360∘=2π radians.
- The area of a portion of a circle. The formula is θ⋅πr2, where θ is the central angle, measured in radians.
- Any change made to an object or graph. Transformations can either be dilations or translations.
- Either a vertical or horizontal movement of an object or function.
- Vertical Shift
- The vertical translation of a function.
- Convert 160∘ to radians.
- Convert 11π12 to degrees.
- Find the exact value of cos3π4.
- Find all possible answers in radians, between 0<θ<2π:tanθ=3√
- This is an image of the state flag of Colorado
- Suppose the radius of the dial of an electric meter on a house is 7 cm.
- How fast is a point on the outside edge of the dial moving if it completes a revolution in 9 seconds?
- Find the angular velocity of a point on the dial.
- In the figure below, there is a quadrilateral formed by four line segments: the two radii of the circle (in pink), the orange segment (marked as “cotangent”), and the green segment (marked as “tangent”). The tangent (green) segment has been constructed as tangent to the circle (forming a 90-degree angle with the radius). How do you know that the number of units that is the length of the cotangent segment is equal to xy? You may assume that the radii shown (pink) are 1 unit.
- Graph y=sinx and y=cosx on the same set of axes over the interval [0,2π]. Where do they intersect?
For questions 13 and 14, find the equation of the graph below. Only sine and cosine functions will have an amplitude other than 1.
Texas Instruments Resources
In the CK-12 Texas Instruments Trigonometry FlexBook® resource, there are graphing calculator activities designed to supplement the objectives for some of the lessons in this chapter. See http://www.ck12.org/flexr/chapter/9700.