Maths Challenge
Maths challenge.net: Perpendicular Construction
This is a "three star" geometry problem where prior math problem skills and proof experience is recommended to solve this "Perpendicular Construction" problem.
Maths Challenge
Maths challenge.net: Tick Tock Triangle
This is a "three star" geometry problem where prior knowledge of probability is required to solve this "Tick Tock Triangle" problem, have fun!
Maths Challenge
Maths challenge.net: Leaning Ladders
Use your right triangle solving skills to solve this ladders in a hole problem.
Maths Challenge
Maths challenge.net: Tri Angles
A geometry proof involving exterior angles of a triangle.
Maths Challenge
Maths challenge.net: Right Triangle Equal Parts
A geometry proof problem involving a right triangle and finding angles of equal measure.
Maths Challenge
Maths challenge.net: Triangle Area
Find the area of this triangle in a coordinate plane.
Maths Challenge
Maths challenge.net: Alley Ladders
This is a "three star" geometry problem where prior math problem skills and proof experience is recommended to solve this relationship between the inverses of heights.
Maths Challenge
Maths challenge.net: Inscribed Rectangle
This is a proof problem, considered a "three star" geometry problem requiring knowledge of proofs and properties of circles to solve this equal area of inscribed polygons problem.
University of Saskatchewan (Canada)
University of Saskatchewan: Techniques for Proofs
The University of Saskatchewan's Department of Mathematics and Statistics provides high school students with online tutorials and exercises on what they deem some of the most important techniques for mathematical proofs: truth tables,...
Maths Challenge
Maths challenge.net: Three Circles
This is a proof problem, considered a "three star" geometry problem requiring knowledge of proofs and properties of circles.
Maths Challenge
Maths challenge.net: Measuring Mountains
Use your triangle solving skills to solve this triangle problem and then apply it to the real world.
Maths Challenge
Maths challenge.net: Isosceles Trapezium
This is a "three star" geometry problem where prior knowledge of problem solving and thinking through proofs is recommended to solve this trapezoid inscribed in a semicircle problem.
Maths Challenge
Maths challenge.net: Rectangular Circles
An area problem involving finding the area of a rectangle and a circle. The problem may be made into a general proof as well.
Maths Challenge
Maths challenge.net: Lunes
A "three star" geometry problem where some experience of math problem solving skills and knowledge of circles is recommended to solve this lunes (parts of a circles) area problem
Stanford University
Stanford Encyclopedia of Philosophy: Gottlob Frege
Good summary of Frege's thought. Some sections are more technical, but the explanation of his philosophy of language and other sections are more readable.
Cuemath
Cuemath: Mathematical Induction
A comprehensive guide for learning all about mathematical induction with definitions, how to prove this formula, solved examples, and practice questions.
Maths Challenge
Maths challenge.net: Peculiar Perimeter
This is a "three star" geometry problem where prior math problem skills and proof experience is recommended. Tile constructions may be used to solve this perimeter and area problem.
Maths Challenge
Maths challenge.net: Corner Circle
This is a "three star" geometry problem where prior knowledge of circles and triangles is recommended to solve this circle in the corner problem.
Math Planet
Math Planet: Geometry: If Then Statement
If-then statements are explained throught the use of examples and a video lesson. [1:16]
CK-12 Foundation
Ck 12: Geometry: Deductive Reasoning
[Free Registration/Login may be required to access all resource tools.] In this lesson students use deductive reasoning to solve problems. Students examine guided notes, review guided practice, watch instructional videos and attempt...
CK-12 Foundation
Ck 12: Analysis: Induction and Inequalities
[Free Registration/Login may be required to access all resource tools.] The transitive property of inequality and induction with inequalities. Students examine guided notes, review guided practice, watch instructional videos and attempt...
CK-12 Foundation
Ck 12: Analysis: Induction and Factors
[Free Registration/Login may be required to access all resource tools.] Students learn to use mathematical induction with integer factoring properties. Students examine guided notes, review guided practice, watch instructional videos and...
CK-12 Foundation
Ck 12: Ferromagnetic Material: Maximizing 4 Pizza Slices
[Free Registration/Login Required] Students explore the concept of conjectures and counterexamples by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn...