工具区
How to open the Tools View
Select the 
Tools View button to open the Tools View.
Tools View button to open the Tools View. Selected GeoGebra Tools
Intersection
To create the intersection point of two objects select the Intersection tool. Click on the two objects to create all intersection points or directly click on an intersection of two objects to only create this single intersection point.
Roots
To find the roots of a function select the Roots tool and click on a function. For polynomials all roots are found, for other functions only those between the left and right edge of the Graphics View.
Extremum
To find the local extrema of a function select the Extremum tool and click on a function. For polynomials all extrema are found, for other functions only those between the left and right edge of the Graphics View.
Note: The coordinates of intersection points, roots and extrema will be displayed in the 
Algebra View.
Slider
To create a slider for a number or an angle select the Slider tool and click on any free space in the Graphics View. The appearing dialog allows you to specify the name, interval and increment of the number and angle.
Note: You can use the name of the number or angle for commands and functions to explore their changes when moving the slider.
Show / Hide Objects
You can hide auxiliary objects in the Graphics View by using the 
Show / Hide Object tool. Activate the tool and select all objects that should be hidden. Then, switch to any other tool to apply your changes.
Delete Object
Use the 
Delete tool to delete unnecessary objects.
Hint: If you select a tool from the Tools View, a Tooltip appears for a few seconds explaining how to use the selected tool.