Plots > Working with Plots > Axes and Tick Marks > To Edit Tick Mark Values
  
To Edit Tick Mark Values
1. On the plot axis to edit, select an editable tick mark value (first one, second one or last one). A cursor appears next to the default tick mark value which turns black.
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Hover over the editable tick marks to see their font size change.
2. Delete the default value.
3. Type a real number or an expression that evaluates to a real number. If you insert a constant (like π), its numeric value is displayed.
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When you edit the first or the last tick marks, the plot viewable range changes. When you edit the first or the second tick mark, the interval between the tick marks changes.
4. Press Enter. All the tick marks of the axis change accordingly.
Additional Information
You may need to repeat this procedure for all the editable tick marks of an axis to get the desired result.
To restore the default value of an editable tick mark, delete its current value and press Enter.