precal Flashcards
Branch of mathematics that studies the relationship between side length and angles of triangles
Widely used in the field of science
Circular Functions
Any amount of rotation generated when a ray is rotated about it’s endpoint
If the arrow is going clockwise it is a negative angle and if it is going counter-clockwise it is a positive angle
Angle
An angle positioned at (0,0) and has an initial side that is alone the positive side of the x-axis
Angles in standard position
A standard angle where the terminal side is on the x or y axis
Quadrantal Angle
Angles that are both in standard position and have the same terminal side
To get a coterminal angle add 360°
Ex. 42° = 42° + 360° = 402° = coterminal angle now :)
Coterminal Angles
Positive angles formed by the terminal side of the given angle and the x-axis
Are acute angles so should be less then or equal to 90°
How to get reference angles in every quadrant
Q1= same
Q2 =180° - θ
Q3= θ - 180°
Q4 = 360° - θ
Reference angles
On a circle of radius ® a central angle(θ) intercepts (s) through the formula of
S = rθ
Central Angle
A sector of a circle is the part of the interior of the circle cut by a central angle whose area A is given by the formula:
A = ½ θr2 , where θ is expressed in rad
Area of a sector
A circle whose center is at the origin and with a radius of 1 unit and every point on the circle satisfies x2 + y2 = 1
If:
x2 + y2 >1 then the point is outside the circle
x2 + y2 = 1 then the point is on the circle
x2 + y2 <1 then the point inside the circle
UNIT CIRCLE
A set of all points in a plane that are equidistant from a fixed point
Circle
(x-h)2 + (y+-k)2 = r2
Center Radius form
An equation that is true for all values of the variables for which every term of the equation is true (ex. 2x + 3x =5x)
Identity
An equation that is true only for some values of the variables for which every term of the equation is defined (ex. x + 3 = 5)
Conditional Equation
