Saturday, March 12, 2011

TI-Nspire CX at T-cubed in San Antonio

At the recent Teachers Teaching with Technology International Conference in San Antonio, I had a great time seeing friends and new technology that will be a blessing to the math and science classroom. There have been questions about how clear is the CX color and backlit screen. To the right you can see a picture I took with my camera. The picture of the flowers were taken by my daughter Lydia in our backyard. This gives new meaning to graphing and rotating a polar 'rose.'

Inserting images makes mathematical modeling a lot more fun. I was showing the picture of the Alamo with the equations on it to a TI-Nspire Online User Group (The next meeting is April 14.), when someone asked about how the circle was draw. When you are on a Graphs or Geometry page you can press menu > Shapes > Circle.
After the circle is draw, you press menu > Actions > Coordinates and Equation and click the circle to show the equation of the circle. I like to move my cursor over the circle and press ctrl menu for right-click and choose Coordinates and Equation. Showing the coordinate or equation is a feature that can be turned off by teachers who do not want students to have access to this. To do this they would use Press-to-Test.

Not that too many high school teachers use 3D by graphing z(x,y), but there is definitely a lot of excitement about this functionality on the TI-Nspire. It is so much more powerful than what was available with the TI-89. When z1(x,y)=x^2+y^2 is entered in the 3D graph view, a paraboloid is almost immediately rendered. This used to take a lot more computing time on the 89. Then something the 89 couldn't do, graph another 3D graph on top of that and z-trace. Auto-rotate by pressing A or just use the arrows.
video Here is a video of a 3D graph that is rotated. I guess I need a better video camera if I want to do any future videos like this. To the right is a much better picture of what the heart looked like on the TI-Nspire CX handheld. (Here is a link for more graphs of hearts.) I was showing this to some middle school students last night. My oldest daughter was begging me to show her friends the CX. Some of her basketball teammates were spending the night on Friday before they went on a service project on Saturday morning. This group of girls said they had never heard of a z-axis. By easily changing the orientation of the axis by pressing x, y, and z or rotating using the arrows, it was fun to watch the 'light bulbs' turn in in their minds. They were so excited about math and learning some things their teachers hadn't taught them. They were exploring and explaining to each other what the z-axis was. With color, images, and fun 3D shapes, math becomes a lot more cool, even for 8th grade girls at a sleep over.

Yes, 3D and the new differential equations graph type, now enabling the drawing of slope fields from anywhere - even the Scratchpad, will be features that are available for the CAS or numeric TI-Nspire or TI-Nspire CX when they upgrade to 3.0.

1 comment:

Anonymous said...

what is the equation of the 3d heart?