Lesson 1
Lesson 2
Lesson 3
Lesson 4
Lesson 5
Definitions, Postulates and Theorems
100

A statement consisting of two clauses, one of which begins with "if" or "when" 

What is a Conditional Statement?

100

A statement formed by interchanging the hypothesis and the conclusion of the conditional. The converse of a true statement is not necessarily true.

Converse of a Conditional Statement

100

A chain of statements, with justification of each statement, that ends with a desired conclusion.

Proof

100

A series of implications leading to a conclusion.

Premise of an arguement

100

The pursuit of logical consequences from a given system of initial universal truths.

Deductive Reasoning

100

Define a Line

Two Points

200

The clause following “if”

Hypothesis

200

Both the conditional statement and its converse are true.

Definition

200

A form of reasoning in which two statements are made and a conclusion is drawn from them.

Syllogism

200

A statement proved to be true by reasoning deductively from already accepted statements.

Theorem

200

A statement proved to be true by reasoning deductively from already accepted statements.

Theorem

200

Define a plane

Three non-colinear points
300

The clause following “then”;

Also, the conditional statement using the first hypothesis and last conclusion of a series of premises.

Conclusion

300

A statement that contains the phrase “if and only if”.”

Bi-conditional Statement

300

A proof in which the conclusion is drawn directly from previous conclusions, starting with the hypothesis of the first premise and ending with the conclusion of the last premise.

Direct proof

300

A proof when an assumption is made at the beginning that leads to a contradiction.  The contradiction indicates that the assumption is false and desired conclusion is true.

Indirect Proof

300

A statement that is assumed to be true without proof.

Postulate

300

The square of the hypotenuse of a right triangle is equal to the squares of the other two sides.

The Pythagorean Theorem

400

A diagram consisting of two circles to represent a conditional statement with the inside circle representing the hypothesis and the outside circle representing the conclusion.

Euler Diagram

400

"iff"

If and only if

400

Reasoning in which a conclusion is reached by stating a general principle and then applying that principle to a specific case.

Deductive Reasoning

400

Assume the opposite of what you are are trying to prove and start listing every consequence that you can think of.  Eventually and error will show up leading to a contradiction and you will be done.

Indirect Proof

400

a2+b2=c2

Pythagorean Theorem

400

The sum of the angles of a triangle is 180°

The Triangle Angle Sum Theorem

500

a rarr b

Symbol for conditional statement

500

a harr b

a If and only if b

500

a rarr b, brarrc,:. ararrc

Syllogism

500

180°

The Sum of the Interior Angles of a Triangle

500

c=2pir

Formula of the Circumference of a circle

500

c=pird 

a=pi r^2

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