the half angle formulas 158 videos

The Euler Formula
Precalculus Polar Coordinates and Complex Numbers
How to use the Euler Formula to convert a complex number from the exponential form to rectangular form.
complex numbers trigonometric form Euler formula e sine cosine modulus argument 
Angles: Types and Labeling
Geometry Geometry Building Blocks
How to label an angle and how to differentiate between acute, right, obtuse, and straight angles.
angle acute right obtuse straight vertex side 
The Midpoint and Distance Formulas in 3D
Precalculus Vectors and Parametric Equations
How to derive the formula for the midpoint of a segment in three dimensions.
position vectors the vector from point a to point b the midpoint formula vector addition scalar multiplication 
Adjacent Angles
Geometry Reasoning, Diagonals, Angles and Parallel Lines
How to define adjacent angles.
vertex side coplanar 
Triangle Side and Angle Inequalities
Geometry Triangles
How to determine the relationship between the side inequalities and angle inequalities in a triangle.
angles smallest to largest sides smallest to largest 
Vertical Angles
Geometry Reasoning, Diagonals, Angles and Parallel Lines
How to define and identify vertical angles.
vertex intersecting lines congruent 
Formulas
PreAlgebra Solving Equations and Inequalities
The importance of solving literal equations for a given variable

Angle Bisectors and Opposite Side Ratios
Geometry Similarity
How to relate the sides of an angle bisected and the lengths of the opposite side.
angle bisector opposite side ratio proportion 
Deriving the Quadratic Formula
Algebra 2 Quadratic Equations and Inequalities
How to derive the quadratic formula by completing the square.
functions domain parent functions inequalities interval notation 
Conic Section Formulas
Algebra 2 Conic Sections
How to identify a conic section by its formula.
parabola circle ellipse hyperbola center focus 
Conic Section Formulas
Precalculus Conic Sections
How to identify a conic section by its formula.
parabola circle ellipse hyperbola center focus 
The Distance Formula in Polar Coordinates
Precalculus Polar Coordinates and Complex Numbers
How to derive the distance formula for polar coordinates.
polar coordinates the law of cosines triangles 
Constructing an Angle Bisector
Geometry Constructions
How to define and construct an angle bisector.
construction perpendicular equidistant shortest distance to a line bisector 
Central Angles and Intercepted Arcs
Geometry Circles
How to define a central angle and find the measure of its intercepted arc; how to describe the intercepted arcs of congruent chords.
chord central angle intercepted arc arc measure congruent chords side side side shortcut 
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 
Change of Base Formula
Algebra 2 Inverse, Exponential and Logarithmic Functions
How to use the change of base formula for logs to evaluate a logarithmic statement.
change of base log logarithm 
Change of Base Formula
Precalculus Exponential and Logarithmic Functions
How to use the change of base formula for logs to evaluate a logarithmic statement.
change of base log logarithm 
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 
Equation of a Circle
Geometry Pythagorean Theorem
How to derive the equation for a circle using the distance formula.
distance formula radius center circle 
Equation of a Circle
Trigonometry Pythagorean Theorem
How to derive the equation for a circle using the distance formula.
distance formula radius center circle