15-8 Equation Writer
(– X) apply to it. As a result, the entered expression is 
interpreted, and displayed, as (2 + X)(3 – X). 
Select the entire expression 
by pressing    and 
evaluate it by pressing 
. The result is:
–(X
2
–X–6)
Example2
To enter X
2
–3X+1, press:
   2   – 3  
+1
If, instead, you had to enter 
–x
2
–3X+1, you would need 
to press:
(–)     2     – 3  +1
Note that you press   twice to ensure that the exponent 
applies to –X and not just to X.
Example 3
Suppose you want to enter:
Each fraction can be viewed 
as a separate branch on the 
equation tree. In the 
Equation Writer type the first 
branch:
1 ÷ 2
and then select this branch by pressing  .
Now type + and enter the second branch: 
1 ÷ 3
Select the second branch by pressing  .
Now type + and enter the third branch: 
1 ÷ 4
Likewise, select the third branch by pressing  , type + 
and then the fourth branch: 
1 ÷ 5
1
2
---
1
3
---
1
4
---
1
5
---
+++
hp40g+.book  Page 8  Friday, December 9, 2005  12:27 AM