TI-84 Plus CE field manual for IB Math
Complex-number arithmetic
Evaluate any numeric complex expression (sums, products, quotients, integer powers, and mixed Cartesian / polar terms) straight off the home screen, provided it contains no unknowns.
Compute (1+2i)3−4eiπ/4 and write the answer in the form a+bi.
Switch the output mode so complex answers are allowed: press , arrow down to the row that starts with REAL, arrow right to a+bi, and press . On the angle row above, make sure RADIAN is highlighted: the eiπ/4 term is only read correctly in radians. Press to return to the home screen.
Type the Cartesian power (1+2i)3: (the arrow steps out of the exponent). The imaginary unit i is the shifted symbol above the decimal key.
Subtract the polar term 4eiπ/4: .
Press to evaluate. Because the output mode is a+bi, the TI-84 folds the power and the polar term into a single Cartesian value.
(1+2i)3−4eiπ/4≈−13.8−4.83i.
Your turn
Work each one on your calculator, then check the answer.
- 1
Compute (2+i)4 in the form a+bi.
- 2
Compute 2+i9−8i in the form a+bi.
- 3
Compute 2eiπ/4+5ei2π/3, giving the answer in polar form reiθ.