### We found 1,657 reviewed resources for proof

Lesson Planet

#### Proof That Geometry Isn't Difficult

Prove that Geometry can be challenging in a good way with a wide-ranging collection of resources on proofs. The topics focus on the main skills while young mathematicians to think outside the box.

Lesson Planet

#### Vertical Angles Proof Samples

This visual, manipulative-based format for teaching geometric proofs nicely scafolds learners' development of mathematical reasoning and proof skills. This sample represents a proof of the congruence of vertical angles in four formats;...

EngageNY

#### Triangle Congruency Proofs (part 2)

Looking to challenge your students that have mastered basic triangle congruence proofs? A collection of proofs employ previously learned definitions, theorems, and properties. Pupils draw on their past experiences with proofs to...

Lesson Planet

#### Flippin' Proofs Parallel Lines Project

Learners will "flip" for this creative way to practice writing and explaining two-column proofs about parallel lines. As they create their masterpiece, young geometers are led to consider overall proof characteristics as well as...

EngageNY

#### Triangle Congruency Proofs (part 1)

Can they put it all together? Ninth graders apply what they know about proofs and triangle congruence to complete these proofs. These proofs go beyond the basic triangle congruence proofs and use various properties, theorems, and...

Lesson Planet

#### Median Concurrence Proof

Develop a proof to show what appears to be true in a drawing actually is true. The assessment asks pupils to draw the three medians of a triangle. Learners develop a proof showing that the point of intersection in their drawing is...

EngageNY

#### Congruence, Proof, and Constructions

This amazingly extensive unit covers a wealth of geometric ground, ranging from constructions to angle properties, triangle theorems, rigid transformations, and fundamentals of formal proofs. Each of the almost-forty lessons is broken...

Lesson Planet

#### Pythagorean Theorem Proofs

Your class knows the Pythagorean Theorem, but can they prove it? A series of three videos shows two proofs of the Pythagorean Theorem and use it to classify triangles.

Lesson Planet

#### Algebraic Proof

Proofs do not exist only in geometry. The video shows the class different ways that proofs appear in algebra. Pupils work through a variety of algebraic proofs involving the divisibility of an algebraic expression or whether it is even...

Lesson Planet

#### Angles in the Same Segment – Proof

If angles intercept the same arc, the angles must be the same size. The quick video talks through the proof of showing the reason two inscribed angles that intersect the same arc have the same measurement. Pupils then create their own...

Lesson Planet

#### Proofs of Derivatives of Ln(x) and e6x

In this video, Sal takes on the challenge of proving both the derivative of ln x = 1/x and of ex = ex, showing that no circular logic is used in the proof. It contains a clearer version of both proofs shown in the videos titled, _Proof...

Lesson Planet

#### Proof: d/dx(x^n)

Using the binomial theorem and definition of a limit, Sal shows a proof that the derivative of xn equals nxn-1.

Lesson Planet

#### Proof: d/dx(e^x) = e6x

Using the derivative of ln x, the chain rule, and the definition of a limit, Sal shows a proof that derivative of ex = ex. Note: The video titled "Proof of Derivatives of Ln(x) and e^x,Ó has a clearer explanation of this proof.

Lesson Planet

#### Proof: d/dx(ln x)=1/x

Using the definition of a limit, various properties of logarithms, and a definition of e, Sal shows the proof of derivative of ln x = 1/x. Note: The video titled "Proof of Derivatives of Ln(x) and e^x,Ó has a clearer explanation of this...

Lesson Planet

#### Proof: d/dx(x^n)

Lesson Planet

#### Quadratic Formula (proof)

This exciting video takes all of the mystery out of the quadratic formula. By watching this video, learners gain an deeper understanding of the quadratic formula and the process of completing the square. Sal shows a step-by-step proof of...

Lesson Planet

#### Angle in a Semi-Circle – Proof

Young mathematicians observe a geometric proof using a short video. They see each part of the diagram clearly labeled and the simple math written off to the side. The new knowledge helps them solve additional problems independently.

Lesson Planet

#### Proofs Of The Pythagorean Theorem?

Even U.S. President James Garfield had his own proof of the Pythagorean Theorem! Pupils consider three different attempts at a geometric proof of the Pythagorean Theorem. They then select the best proof and write paragraphs detailing...

EngageNY

#### Informal Proof of the Pythagorean Theorem

Prove the Pythagorean Theorem using multiple informal proofs. Scholars first develop an understanding of the origins of the Pythagorean Theorem through proofs. They round out the lesson by using the theorem to find missing side lengths...

EngageNY

#### Informal Proofs of Properties of Dilations

Challenge the class to prove that the dilation properties always hold. The lesson develops an informal proof of the properties of dilations through a discussion. Two of the proofs are verified with each class member performing the...

Lesson Planet

#### Justifying a Proof of the AA Similarity Theorem

Why are two triangles with congruent angles similar? Class members provide the justifications or explanations of the steps of a proof of the AA Similarity Theorem. The proof uses transformations as a basis to proving the theorem.

Lesson Planet

#### Proof

Scholars learn how to write number theory proofs by viewing a video reviewing techniques for proofs on divisibility, parity, and consecutive integers. They then write proofs for a handful of conjectures on a worksheet.

Lesson Planet

#### Proof with Parallelogram Vertices

Geometric figures are perfect to use for proofs. Scholars prove conjectures about whether given points lie on a triangle and about midpoints. They use a provided dialogue among fictional students to frame their responses.

Lesson Planet

#### Pythagorean Theorem Proof

No geometry class is complete without a proof. A short video in the Socratica Geometry playlist covers an algebraic proof of the Pythagorean Theorem. Simplifying an equation with two equivalent expressions for the area of a square leads...