angle measure 109 videos

Evaluating Sine and Cosine at Special Acute Angles
Precalculus Trigonometric Functions
How do we measure sine and cosine of pi/4?
sine cosine unit circle definitions of sine and cosine angles in standard position 
Other Forms of the Cosine DoubleAngle Formula
Precalculus Advanced Trigonometry
How to derive two more cosine doubleangle formulas.
the Pythagorean identity the cosine double angle formulas 
Other Forms of the Cosine DoubleAngle Formula
Trigonometry Advanced Trigonometry
How to derive two more cosine doubleangle formulas.
the Pythagorean identity the cosine double angle formulas 
Constructing an Angle Bisector
Geometry Constructions
How to define and construct an angle bisector.
construction perpendicular equidistant shortest distance to a line bisector 
The Angle Between Planes
Precalculus Vectors and Parametric Equations
How to find the angle between planes, and how to determine if two planes are parallel or perpendicular.
normal vector the angle between planes perpendicular planes dot product scalar multiple parallel planes 
Same Side Interior and Same Side Exterior Angles
Geometry Reasoning, Diagonals, Angles and Parallel Lines
How to describe same side interior and same side exterior angles and their special properties.
parallel lines angles congruence interior exterior transversal 
The Definitions of Sine and Cosine
Trigonometry Trigonometric Functions
How we define sine and cosine for all angle measures using the unit circle.
sine cosine right triangle definitions of sine and cosine angles in standard position unit circle definitions of sine and cosine 
The Definitions of Sine and Cosine
Precalculus Trigonometric Functions
How we define sine and cosine for all angle measures using the unit circle.
sine cosine right triangle definitions of sine and cosine angles in standard position unit circle definitions of sine and cosine 
Types of Triangles
Geometry Geometry Building Blocks
How to classify a triangle based on its side lengths and angle measures.
equiangular equilateral isosceles right acute obtuse triangles 
Equiangular Polygon Sums
Geometry Polygons
How to find the measure of one angle in any equiangular or regular polygon.
equiangular regular congruent triangles sum 
Arc Length
Geometry Circles
How to define arc length and how it is different from arc measure; how to calculate the length of an arc.
arc length arc measure concentric circles fraction circumference radius diameter 
Charge Transfer  Electroscope
Physics Electricity
Understanding how charge is transferred through an electroscope.
charge transfer electroscope measure 
Mean
Algebra Introduction to Statistics
How to calculate the mean, or average, of a list of numbers.
mean measure of center average 
Median
Algebra Introduction to Statistics
How to calculate the median of a data set.
median measure of center 

Cyclic Quadrilaterals and Parallel Lines in Circles
Geometry Circles
How to prove that opposite angles in a cyclic quadrilateral are congruent; how to prove that parallel lines create congruent arcs in a circle.
inscribed angles cyclic quadrilaterals parallel lines alternate interior angles 
Special Isosceles Triangle Properties
Geometry Triangles
How to identify a segment from the vertex angle in an isosceles triangle to the opposite side.
isosceles triangle angle bisector altitude median 
Corresponding Parts of Similar Triangles
Geometry Similarity
How to relate corresponding altitudes, medians and angle bisectors in similar triangles.
similar triangles altitude median angle bisector proportional 
ASA and AAS
Geometry Triangles
How to use the ASA and AAS shortcuts to determine the congruence of two triangles.
triangle congruence angle side angle angle angle side 
Radii to Tangents
Geometry Circles
How to define a tangent line; how to determine the angle a radius to a tangent forms.
tangent radius right angle point outside the circle perpendicular