Start Up Info and Tasks

Algebra Start with a new window. Doing algebra on GeoGebra is like having the world’s best graphing calculator. Input Bar: the open bar at the bottom of the program is called the input bar. What you type there is computed or created in the sketch. •

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Point. Have open the graphics window and the algebra view. As you try the steps below, observe: What do you notice? o (2,3) o A=(3,3) (What happened to the name of the first point?) o (pi, cos(pi)) o Drag one of your created points to move it. o Select one of the points and use an arrow key. Try shift+arrow. Line. You may want to clear off the previous points. You can delete from the graphics or algebra window. You can drag the arrow tool to select multiple objects at a time. Or you can always make a new window and then close the old. o Input a line in slope-intercept form. (Eg., y=3x – 1) o Input a line in standard form. (Eg., 6x – 5y = 10) o Input a crazy mixed up equation. (Eg. 4x – 2y +3 = 10 +3y – 2x – 2) o Create 2 points, and try Line[,] where is the name you or GeoGebra gave the first point, etc. o Drag one of your lines to move it. Function. May want a clear window. o Check out the pre-defined functions available.   o Try y= (function of your choice; The ^ is for exponents, such as x^3=x3 ) o Try z= … o Try f(x)=… o Give a function a specific name, like distance(x)=… o Try different variable names. o Try an implicitly defined function (Maybe x y^2- x- y^3 = 0) o Drag one or more of your functions. Properties: • Open the properties box for a point. What can you change? Note the different tabs in the property box. • Open the properties box for a function. Make it standout!

Beginning Algebra Tasks 1) Solve a system of linear equations by using GeoGebra to find the intersection. 2) Find a cubic function with exactly two roots, one positive and one negative, by playing with the coefficients in standard form. 3) Make two points and a linear function that goes through them regardless of how the points are moved. Make another, and then a third function that is the product of the first two. (Note that GeoGebra treats equations and functions differently.) Geometry Start with a new window. Doing geometry on GeoGebra is like having a magic straightedge and compass. Geometry Tools: 1) Line Tool: draw a line. Switch line tools and draw a ray and line segment. For one of them, use an existing point as the first or second point. 2) Use the point tool option to find the midpoint of two of your points. 3) Use the perpendicular line tool and the parallel line tool to construct new lines. 4) Use the polygon tool to make a polygon with new points, and another using some existing points. 5) Construct a circle using the two point tool, and another with the circle with a center an radius tool. 6) Measure an angle, an area and a distance. 7) Try to figure out how to use the rotation tool, the reflection tool, and/or the translation tool. 8) Delete everything and make a new picture. Properties: • Open the properties box for a point. What can you change? Note the different tabs in the property box. • Open the properties box for a polygon. Make it standout!

Beginning Geometry tasks: 1) Using only points, circles and lines, construct the vertices of an equilateral triangle. Make one that can change size. 2) Construct a dynamic parallelogram. 3) Construct a dynamic kite.