Write the expression 2i^15-i^7 in the standard form a + bi

1 answer:

7 0

$\bf 2i^{15}-i^7\qquad 
\begin{cases}
i^2=\sqrt{-1}\cdot \sqrt{-1}\implies \sqrt{(-1)^2}\implies -1\\\\
i^4=i^2\cdot i^2\implies -1\cdot -1\implies 1
\end{cases}\\\\
-----------------------------\\\\
2i^{4+4+4+2+1}-i^{4+2+1}\implies 2i^4i^4i^4i^2i^1-i^4i^2i^1
\\\\\\
(2\cdot 1\cdot 1\cdot 1\cdot -1\cdot i)-(1\cdot -1\cdot i)\implies -2i-(-i)
\\\\\\
-2i+i\implies -i\implies \boxed{0-i}$

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Multiply the values of a and c together;

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270= 3*3*3*5*2

Now find a way to add these factors in different ways to give 33 (b value)

We can try (3*3*2)+(3*5)=?

18+15=33

Now that you know the numbers, break down the b value.

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Answer:

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Step-by-step explanation:

Given:

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KonstantinChe [14]

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dezoksy [38]

Answer:

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