CHAPTER 0
Calculator Notes for the TI-Nspire and TI-Nspire CAS
Note 0A: Fractions and Decimals
You can use the handheld to perform operations with both fractions and
decimals. If your handheld or document is set to Auto, it will automatically
display division calculations as fractions in lowest terms. If it is set to
Approximate, it will display them as decimal approximations. To learn
how to change settings, see the Getting Started note.
Using Fractions in the Calculator Application
Press
1.
c and choose Calculator. There are two ways to enter a fraction.
Type the numerator, press p, then type the denominator. Press ·.
In Auto setting, the calculation is displayed as a fraction in lowest terms.
Press /· to display the decimal equivalent.
2. Press /p. A fraction template will appear. Type the numerator,
press ¤, and type the denominator. Press ¢ to exit the fraction template. In
Auto setting, press · to display the number as a fraction in lowest terms
or /· to display the decimal equivalent.
The second method might seem complicated for a simple fraction, but it is
useful when the fraction is complex or the numerator and denominator
contain expressions.
(continued)
Discovering Advanced Algebra Calculator Notes for the Texas Instruments TI-Nspire and TI-Nspire CAS
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Note 0A: Fractions and Decimals (continued)
TI-Nspire and TI-Nspire CAS
If your handheld or document is set to Approximate, it will always convert a
fraction to a decimal.
Using Fractions in the Lists & Spreadsheet Application
Press c and choose Lists & Spreadsheet. To input a fraction in the Lists &
Spreadsheet application, type the numerator, press p, type the
denominator, and press ·. If you are in Auto setting, the calculation is
displayed as a fraction. You cannot approximate the fraction by pressing
/·. If you are in Approximate setting, the calculation is displayed as a
decimal approximation.
Note 0B: Order of Operations
To evaluate expressions, the handheld uses the standard order of operations,
PEMDAS, which is parentheses, exponents, multiplication and division, and
addition and subtraction. For example, when you enter the expression
1 + 12 / 4 3:
a. The handheld reads no parentheses or exponents.
b. The handheld multiplies and divides from left to right, so it evaluates 12 / 4
as 3 to get 1 + 3 3, and it evaluates 3 3 as 9 to get 1 ⫹ 9.
c. The handheld adds and subtracts from left to right, so it evaluates 1 ⫹ 9
as 10.
(continued)
8
CHAPTER 0
Discovering Advanced Algebra Calculator Notes for the Texas Instruments TI-Nspire and TI-Nspire CAS
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Note 0B: Order of Operations (continued)
TI-Nspire and TI-Nspire CAS
Negation is on the same level as multiplication, so powers are calculated
before negation. So the handheld evaluates ⫺42 as ⫺16, but evaluates (⫺4)2
as 16.
Although there are keys for the brackets and braces you may use for
grouping when you work on paper, the handheld uses them for other things.
To group on the handheld, you use only parentheses, but you can also enter
expressions as they appear in your_____
book. Here are two equivalent ways to
8 ⫹ 1 ⫺ 4
5⫹3
____
________
evaluate the expression 2 4 ⫹ [ 2(7 ⫺ 2) ] 2 .
1. Press /p, type 5 + 3, press ¤, type 2 4, press ¢ +,
press /p/q, type 8+1, press ¢, type – 4, press ¤,
type (2(7 – 2)), and press q·.
2. Type (5 + 3) / (2 4) + (, press /q, type 8 + 1, press ¢,
type – 4) / (2(7 – 2)), and press q·.
Discovering Advanced Algebra Calculator Notes for the Texas Instruments TI-Nspire and TI-Nspire CAS
CHAPTER 0
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