hp40g+.book Page 4 Friday, December 9, 2005 1:03 AM

Example 3

Press to evaluate the selection.

It remains to transform 312 and combine it

with –63 . Follow the same procedure as undertaken a number of

times above. You will find that 312 is equal to

63 , and so the final two terms cancel each other out.

Hence the result is

C= 45

Given the expression D = (3x – 1)2 – 81 :

•expand and reduce D

•factor D

• solve the equation (3x – 10) ⋅ (3x + 8) = 0 and

•evaluate D for x = 5.

Solution: First, enter D using the Equation Writer:

3 X 1

2 81

Press

to select

(3X – 1)2 and to expand the expression. This gives: 9x2 – 6x + 1 – 81

16-4

 

 

Step-by-Step Examples