User Manual

2-32
6. Complex Number Calculations
You can perform addition, subtraction, multiplication, division, parentheses calculations,
function calculations, and memory calculations with complex numbers just as you do with the
manual calculations described on pages 2-1 to 2-16.
You can select the complex number calculation mode by changing the Complex Mode item on
the Setup screen to one of the following settings.
• { Real } ... Calculation in the real number range only*
1
• { a + bi } ... Performs complex number calculation and displays results in rectangular form
• {
r ∠  } ... Performs complex number calculation and displays results in polar form*
2
*
1
When there is an imaginary number in the argument, however, complex number calculation
is performed and the result is displayed using rectangular form.
Examples:
ln 2
i = 0.6931471806 + 1.570796327 i
ln 2 i + ln (– 2) = (Non-Real ERROR)
*
2
The display range of  depends on the angle unit set for the Angle item on the Setup
screen.
• Deg ... –180 <
 < 180
• Rad ... – π <
 < π
• Gra ... –200 <
 < 200
Press K3(CPLX) ( K2(CPLX) on the fx-7400GIII) to display the complex calculation
number menu, which contains the following items.
• { i } ... {imaginary unit i input}
• { Abs } / { Arg } ... obtains {absolute value}/{argument}
• { Conj } ... {obtains conjugate}
• { ReP } / { ImP } ... {real}/{imaginary} part extraction
• { '
r ∠  } / { 'a + bi } ... converts the result to {polar}/{rectangular} form
• You can also use !a( i ) in place of K3(CPLX) ( K2(CPLX) on the fx-7400GIII)
1( i ).
• Solutions obtained by the Real,
a+bi and r∠ modes are different for power root (
x
')
calculations when x < 0 and y = m/n when n is an odd number.
Example: 3
x
' (– 8) = – 2 (Real)
= 1 + 1.732050808 i ( a + b i )
= 2 ∠ 60 ( r ∠  )
• To input the “ ∠ ” operator into the polar coordinate expression (
r ∠  ), press !v( ∠ ).