Answer:
0 +256i
Step-by-step explanation:
According to Euler's formula, ...
(4 cis π/8)^4 = (4^4) cis (4×π/8) = 256 cis π/2 = 0 +256i
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"cis" is an abbreviation sometimes used for "cosine + i×sine". It simplifies writing the expression. Engineers sometimes simplify it further, writing 4∠(π/8) for the expression in this problem statement.
