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Tag Archives: similarity
Cubes in onepoint perspective
This post is a reply to Jamie’s comment on Drawn to Math: Would anyone know how to construct a cube in one point perspective? This is an excellent question because it isolates an important, simplified situation that enables one to study key aspects of … Continue reading
Posted in applied math, math
Tagged cubes, geometry, onepoint perspective, perspective drawing, similarity
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Do you believe this?
Here’s a triangle: I’ll use the vertex labels to also denote the corresponding angle measures. Take the sines of all 3 angles in the triangle: , , and . Would you believe it if I told you that these three … Continue reading
Posted in Contest Math, math
Tagged law of cosines, Ptolemy's theorem, similarity, sine, triangles, trigonometry
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Use Your Mind to Save Yourself Time
I’m looking forward to Games Night at the Math Prize for Girls coming up this weekend. I’ve been working with the author of “Mess or Math?” to create a really fun math activity and I hope many of you who … Continue reading
Posted in Contest Math, math, Math Education
Tagged AMC 12, circles, circumference, geometry, similarity, tangent circles
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The Number Plane
If you’ve got an adventurous spirit and are happy not knowing where things may be going, I suggest skipping the blue paragraph and going straight to The Number Line. We present a geometric approach to introducing complex numbers. The approach … Continue reading
Posted in math, Math Education
Tagged complex numbers, geometry, number plane, parallelogram law, similarity, square root of 1
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Similarity Simplifies
When you see that two figures are similar to each other, everything becomes simpler. Suddenly, you realize that if you understand one figure, you know everything about the other, except for its absolute size. I was observing some students solving … Continue reading
Posted in Contest Math, math, Math Education
Tagged geometry, Pythagorean theorem, similarity
1 Comment
Circles, Squares, and Parabolas
If you take two circles, you can position them before your right eye in such a way that one will perfectly overlap the other. In other words, a circle is geometrically similar to all other circles. The same is true … Continue reading