Equation Writer Selection Mode

To manipulation of mathematical expression and the four arrow keys as enabling you move through the tree in a natural fashion:

• The right and left arrow keys enable you to move from one branch to another.
• The up and down arrow keys enable you to go up and down a particular tree.
• The SHIFT-up and SHIFT-down arrow keys enable you to make multiple selection.

To enter the following expression using Equation Writer on HP 40gs:

Press CAS on the menu bar to open the Equation Writer, then type the first branch:
[1] [divide] [2]
then select this branch by typing the [Up Arrow] key twice.
Then, type
[+]
and the second branch:
[1] [divide] [3]
then select this branch by typing the [Up Arrow] key twice.
Then, type
[+]
and the third branch:
[1] [divide] [4]
then select this branch by typing the [Up Arrow] key twice.
Then, type
[+]
and the fourth branch:
[1] [divide] [5]
then select this branch by typing the [Up Arrow] key three times to select the entire expression.

Press [ENTER] to solve.