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3 years ago

Hey I need help with this problem pls.

Mathematics

1 answer:

Goryan [66]3 years ago

8 0

Step-by-step explanation:

=2√-28

=2√4×7×-1

=2(2)√7×-1

=4i√7 (i=√-1)

<h3>Note:if you need to ask any question please let me know.</h3>

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Klio2033 [76]

Answer:

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Step-by-step explanation:

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anyanavicka [17]

Answer:

See the proof below

Step-by-step explanation:

For this case we need to proof the following identity:

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$tan (x) =\frac{sin(x)}{cos(x)}$

So we can replace into our formula and we got:

$tan(x-y) = \frac{sin(x-y)}{cos(x-y)}$ (1)

We have the following identities useful for this case:

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Now we can divide the numerator and denominato from expression (2) by $\frac{1}{cos(x) cos(y)}$ and we got this:

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Answer:

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Step-by-step explanation:

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