Some important notes on complex mode and modulas,argument determination

Model : CASIO fx-570MS, CASIO fx-991MS, CASIO  fx-100MS

Note 1: Expression can be stored in CALC memory in complex mode.

Note 2: Variables A,B,C and M can be used in COMPLEX mode. Variables D,E,F,X,Y won't appear in COMPLEX mode.

Note  3: The indicator R↔I in the upper right corner of a calculation result display indicates a complex number result.

Note 4: Direct calculation of (a+ib)ⁿ will show mathematical error.

Example: Compute modulas and argument of the complex number -3+2i. (Ans: 3.606 and 146.31 Degree)

Solution:

(Mode initialization)

MODE >> 2(CMPLX)

(Calculation)
SHIFT >> ) >> ( >> - >> 3 >> + >> 2 >> ENG >> ) >> = (Modulas)

SHIFT >> ( >> ( >> - >> 3 >> + >> 2 >> ENG >> ) >> = (Argument)

Example: Calculate (3-2i)⁷. (Ans: -4449+6554i )

(If we try to calculate this directly by operating (3-2i) >> ∧ >> 7 calculator will show mathematical error)

(Mode initialization)
MODE >> 2(CMPLX)


(Calculation)
( >> 3 >> - >> 2 >> ENG >> ) >> SHIFT >> x²  >> = (here we get (3-2i)³ ) >> x² >> = (here we get (3-2i)⁶ ) >> * >> ( >> 3 >> - >> 2 >> ENG >> ) >> = (Real part of result ) >> SHIFT >> = (imaginary part of result )



In EQN MODE if you solve an equation that has complex roots there will be a sign R↔I in the upper right corner indicating complex numbers.In the same manner pressing Shift >> = will give you the imaginary part of result.