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3 years ago

Using De-Moivre's theorem, prove that i^2= -1.

Mathematics

1 answer:

Novosadov [1.4K]3 years ago

3 0

Write i in trigonometric form. Since |i| = 1 and arg(i) = π/2, we have

i = exp(i π/2) = cos(π/2) + i sin(π/2)

By DeMoivre's theorem,

i² = exp(i π/2)² = exp(i π) = cos(π) + i sin(π)

and it follows that i² = -1 since cos(π) = -1 and sin(π) = 0.

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Step-by-step explanation:

Let a represent adult tickets

Let c represent child tickets

On the first day she sells 6 adult tickets and 5 children tickets for total of 112.50. This can be written as:

6a + 5c = 112.50 ...... equation i

On the second day she sells 8 adult tickets and 4 children tickets for the total 130. This can be written as:

8a + 4c = 130 ....... equation ii

6a + 5c = 112.50 ...... equation i

8a + 4c = 130 ....... equation ii

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3 years ago

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Translate it

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3 years ago

Using De-Moivre's theorem, prove that i^2= -1.​

Using De-Moivre's theorem, prove that i^2= -1.