Answer:
i think this is what u are,asking
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.
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Answer:
7k
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Step-by-step explanation:
We are trying to combine like terms with the expression: -k - ( - 8k)
We are pretty much solving it.
Solve:
-k - ( - 8k)
The "- ( -" turns into a plus sign.
So it would look like:
-k - -8k or -k + 8k
Now, you would finish solving
-k + 8k = 7k
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