Steve Stein
I am a math teacher and tutor from Brooklyn, NY.
Hyperbola Foci (Focal Points), Ellipses vs. Hyperbolas (Conic Sections / Precalculus / Lesson 11)
Vertical Hyperbolas (and the Transverse Axis) (Precalculus / Conic Sections / Lesson 10)
Horizontal Hyperbolas, Asymptotes (Precalculus / Conic Sections / Lesson 9)
The Concept of Eccentricity (Precalculus / Conic Sections / Lesson 8)
The Focal Points (Foci) of an Ellipse (Precalculus / Conic Sections / Lesson 7)
Ellipses as Stretched Circles (Precalculus / Conic Sections / Lesson 6)
Parabola Form Conversion (Precalculus, Conic Sections, Lesson 5)
Parabola Focal Width / Latus Rectum and Intercepts (Precalculus / Conic Sections / Lesson 4)
Shifted and Horizontal Parabolas (Precalculus, Conic Sections, Lesson 3)
Parabola Focus/Directrix Definition and Formula (Precalculus, Conic Sections, Lesson 2)
An Exploratory Introduction to the Conic Sections (Precalculus, Conic Sections, Lesson 1)
Continuous and Uniformly Continuous Functions
Why Angle-Side-Side Doesn't Work (And Sometimes Does!)
Euclid's Division Lemma Proof
Archimedes' Proof that the Area of a Circle is πr^2
Challenging But Accessible Math Problems: Grouping Weights
Deriving the Pythagorean Identities (Trigonometry)
Where is Sine/Cosine Positive or Negative?
Trigonometric Functions and the Unit Circle - Example (Cosine of 120 Degrees)
Trigonometric Functions and the Unit Circle - Conceptual Introduction
Cosine of the Difference of Two Angles (Proof)
The Law of Cosines - Proof
Combinations (vs. Permutations)
Permutations
Absolute Value - Equations, Inequalities, "Distance"
Linear Equations - Point-Slope Form
Factoring I - (Greatest) Common Factor
Linear Equations - Slope-Intercept Form
Linear Equations - y-Intercepts
Linear Equations - Slope