3. Patterns in shapes

1.  Using the Fibonacci nos. to make a golden rectangle (chapter 7)


2.  Using the pentagon to get the golden mean (also similar triangles)


3.  The golden spiral from a pentagon (chapter 7)


4.  Start the binomial expansion using the area of a square, and volume of a cube


5.  Number of routes between points...taxicab geometry, people pieces, lead to Pascal's triangle (chapter 9)


6.  Following Archimedes to get Pi


7.  Area within shapes on a geoboard, leads to integral! (see also Geoboard Magic)


8.  Find the slope of a ramp (or mountain,..)


9.    # of images in the hinged mirrors vs the angle between the mirrors


10.  How lengths, squares and cubes grow (chapter 6). See also Genny doubles the size of a dog


11.  The surface area to volume ratios of  the Cuisenaire rods to find out why rodents are nocturnal animals (chapter 6)


12.
Fractals- finding the area and perimeter of the snowflake curve and see Emily's work on the same and the IES java applet inspired by Don's chapter 11 .


13. How the Nautilus shell grows (chapter 6)- similar shapes within the Nautilus shell. See
the 'eye test' for similar shapes in Chapter 11.

 14. Using a Pantograph (similar shapes) by Roxana and by Sheri.


15. Finding the area of rectangles with a constant perimeter (chapter 14).


16. Using squares and pieces of squares to find fractions which lead to infinite series


17. Finding the angle formed two chords in a circle


18. Using squares and rectangles to multiply fractions


19. Volume of a pyramid is 1/3 the Volume of a cube with the same base and height (Sheri's work) and see 


20. See Abe's work on tessellations 

21. Geometric transformations with matrices: Justin works on reflections with matrices . Also see Don's sample problems from his book "Changing Shapes With Matrices"

22.. Finding the sum of the angles of a polygon. See Paul's work

23. spirals

i. Nautilus shell

Study growth

a). in size of chamber, by finding ratios of radius vectors 360' apart and

b). in volume by pouring water in chambers

c). the angle between the radius vector and the tangent to the curve

Graph of  exCot(79.5*Pi/180) and the Nautilus shell

ii. Graph (1+i)n   See chapter 11

iii. Graph of ii i...  and the IES java applet inspired by Don's chapter 11

iv. Graph of  r = 2in chapter 11, the polar graph of a spiral and shows the ratios of the areas of 90' segments. See "On Size and Life" by McMahan & Bonner; Scientific American Library Series; W.H. Freeman and Co., NY, NY; pp 47-51

24. Olivia makes a 3x3x3 cube with the Soma pieces.

25. Anna: " the sum of the angles of a triangle is not always equal to 180' " 


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