Hi,

I tried to express tan(5 ) in terms of tan( ) but ican't do it, can you help me please??

Thanks.

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- Oct 4th 2010, 04:25 PM #1

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- Oct 4th 2010, 06:20 PM #2

- Oct 4th 2010, 07:39 PM #3

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Hello, lehder!

If we are allowed to use DeMoivre's Theorem,

. . there is a clever solution.

We are told that: .

Expand the right side:

. .

. . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . .

Equate real and imaginary components:

. .

We have: .

. . . . . . . . . . . . .

Divide numerator and denominator by

. .

. .