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�<br />

often frustrating if one lost minus sign or decimal point invalidates the<br />

solution. Fortunately, technologists of today have calculators and computer<br />

methods that make the process measurably easier with higher<br />

degrees of reliability and accuracy.<br />

Calculators<br />

CALCULATOR AND COMPUTER METHODS WITH COMPLEX NUMBERS ⏐⏐⏐ 607<br />

The TI-86 calculator of Fig. 14.58 is only one of numerous calculators<br />

that can convert from one form to another and perform lengthy calculations<br />

with complex numbers in a concise, neat form. Not all of the<br />

details of using a specific calculator will be included here because each<br />

has its own format and sequence of steps. However, the basic operations<br />

with the TI-86 will be included primarily to demonstrate the ease with<br />

which the conversions can be made and the format for more complex<br />

operations.<br />

For the TI-86 calculator, one must first call up the 2nd function<br />

CPLX from the keyboard, which results in a menu at the bottom of the<br />

display including conj, real, imag, abs, and angle. If we choose the key<br />

MORE, � Rec and � Pol will appear as options (for the conversion<br />

process). To convert from one form to another, simply enter the current<br />

form in brackets with a comma between components for the rectangular<br />

form and an angle symbol for the polar form. Follow this form with<br />

the operation to be performed, and press the ENTER key—the result<br />

will appear on the screen in the desired format.<br />

EXAMPLE 14.27 This example is for demonstration purposes only. It<br />

is not expected that all readers will have a TI-86 calculator. The sole<br />

purpose of the example is to demonstrate the power of today’s calculators.<br />

Using the TI-86 calculator, perform the following conversions:<br />

a. 3 � j 4 to polar form.<br />

b. 0.006 �20.6° to rectangular form.<br />

Solutions:<br />

a. The TI-86 display for part (a) is the following:<br />

(3, �4) � Pol ENTER<br />

(5.000E0��53.130E0)<br />

CALC. 14.1<br />

b. The TI-86 display for part (b) is the following:<br />

(0.006�20.6) � Rec ENTER<br />

(5.616E�3, 2.111E�3)<br />

CALC. 14.2<br />

EXAMPLE 14.28 Using the TI-86 calculator, perform the desired<br />

operations required in part (c) of Example 14.26, and compare solutions.<br />

Solution: One must now be aware of the hierarchy of mathematical<br />

operations. In other words, in which sequence will the calculator perform<br />

the desired operations? In most cases, the sequence is the same as<br />

FIG. 14.58<br />

TI-86 scientific calculator. (Courtesy of Texas<br />

Instruments, Inc.)

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