Texas Instruments TITANIUM TI-89 User Manual

Page 264

Symbolic Manipulation

264

Finding Proper Fractions and Common Denominators

Use the

propFrac

(

„

) and

comDenom

(

„

) functions.

In this example:

Find a proper fraction for the expression
(

+ x) / (2x

+ x + 4)

Then transform the answer into a ratio of a
fully expanded numerator and a fully
expanded denominator.

Notice that

propFrac

and

comDenom

perform

opposite operations.

Note:

You can use

comDenom

with an

expression, list, or matrix.

propFrac(rational expression

var

]

)

for proper fractions with respect
to a variable

comDenom(expression

var

]

)

for common denominators that collect
similar powers of this variable

If you do this example
on your handheld, the
propFrac function
scrolls off the top of the
screen.