HP 40gs User Manual page 260

hp40g+.book Page 8 Friday, December 9, 2005 1:03 AM
15-8
(– 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:
2
–(X –X–6)
Example2
2
To enter X –3X+1, press:
2 – 3
+1
If, instead, you had to enter
2
–x –3X+1, you would need
to press:
(–) 2
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:
1
-- -
+ + +
2
Each fraction can be viewed
as a separate branch on the
equation tree. In the
Equation Writer type the first
branch:
and then select this branch by pressing
Now type + and enter the second branch:
Select the second branch by pressing
Now type + and enter the third branch:
Likewise, select the third branch by pressing
and then the fourth branch:
– 3 +1
1 1 1
-- - -- - -- -
3 4 5
1 ÷ 2
.
1 ÷ 3
.
1 ÷ 4
, type +
1 ÷ 5
Equation Writer