Unit 1 vocab Flashcards
Angle
Formed by two rays that have a common endpoint
Two sides of angles
Initial side and terminal side
Vertex
Origin of angle
Positive angle
Generated by counterclockwise rotation
Negative angle
Generated by clockwise rotation
Quadrantal angle
An angle where the terminal side lies on the x-axis or the y-axis
Acute angle
Measures less than 90
Right angle
90 degree measure
Obtuse angle
180 > measure > 90
Straight angle
Standard position
An angle where its vertex is at the origin and its initial side lies along the positive x-axis
Central angle
An angle whose vertex is the the center of a circle
Radian measure
The measure of the intercepted arc’s length divided by the circle’s radius
Angle measures
Amount of rotation from initial to terminal side
1 radian
Measure of the central angle = length to the radius of the circle = 1 radian
Measure of central angle
Arc length (s) / circle radius (r) = theta
Degrees to radians
Degrees * (pi radians / 180 deg) = radians
Radians to degrees
Radians * (180 deg / pi radians) = degrees
Arc length
Circle radius (r) * radian central angle (theta) = s
Coterminal Angles
Two angle with the same initial and terminal sides but possibly different rotations
Even functions
1) Symmetric with around y-axis
2) (x,y)=(-x,y)
Odd function
1) Symmetric around the origin
2) (x,y) = (-x,-y)
Pythagorean Identities
1) sin^2t + cos^2t = 1
2) 1 + tan^2t = sec^2t
3) 1 + cot^2t = csc^2t
Periodic functions
The function circles back around to the same quadrant
