Open the wrench and turn on Complex Mode before you type i. Off, i is just a letter. The wrench as a set is in the settings wrench.
Mode first, then the expression
(2 + 3i)(2 − 3i) will compute only after Complex Mode is on. Complex numbers as a set are in complex numbers. Store a leftover value on its own line, in store a value.
Desmos as a tool is in Desmos on the ACT.
The bottom line
Wrench, Complex Mode, then type i. Do not hunt i on a blank graph.
Start practicing
Start with a free diagnostic, then drill your weak spots with 15-question quizzes and track how you're doing across Reading, English, and Math. Compare plans whenever you're ready to go further.
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