Got back trig tests, spent class remediating, correcting, and reassessing trig topics.
Homework
start studying/memorizing these formulas: bit.ly/formulas18
Started unit on area/volume/3D with a 3 act task related to two glasses of soda. Looked at what the meaning of π really is and used it to find the reason behind the circumference formula being C=2πr. Then looked at different methods for proving the area of a circle being πr^2 through subdividing a circle into little 'pizza slices' (sectors) or 'onion rings' (concentric circles) and rearranging to either a rectangle or a triangle with the base being part or all of the circumference. Made the connection that a cylinder is just a stack of circles so the volume is the circle area times the height of the stack. Closed with another 3 act task dealing with cylinders with the same surface area.
Notes from board
Homework
p. 475 #1-6, 11
Continue studying these formulas: http://bit.ly/formulas18
Animations and videos watched in class:
meaning of pi
circumference showing 2π radii
area of a circle by rearranged slices
video of area of a circle by rearranged slices
interactive area of a circle applet
circle area unraveled into triangle
circle intro triangle video
HW Help Resources
find circumference given area: link
find area given circumference: link
Warm up was to find circumference from area and vice versa. Went over homework, the learned about cylinder surface area, cone volume, and cone surface area.
Notes from board
Homework
p. 505 #3,8,10
p. 521 #3,4,8
next assessment: Tues/Wed
continue studying formulas: http://bit.ly/formulas18
Resources
cone surface area: link
cylinder surface area: link
cylinder volume: starts at 2:25
cone volume: link
find circumference given area: link
lateral (rectangular) surface area of cylinder: link
rectangular prism surface area: link
cylinder surface area: link