Question
Asked Dec 8, 2019
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Have both question and answer (second picture), but need help knowing how to get that answer using laplace transform methods

|17. f(1) = cos² 21
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|17. f(1) = cos² 21

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17. cos? 21 = (1+ cos 47); [s-1 +s/(s² + 16)].
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17. cos? 21 = (1+ cos 47); [s-1 +s/(s² + 16)].

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Expert Answer

Step 1

The given function,

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f (t) = cos 2t

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Step 2

Using the formula in the following,

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cos 4t = 2 cos² 2t – 1 (1+ cos 41) cos 2t =

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Step 3

Therefore...

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f (t) = cos 21 S() = ÷(1+ cos 4r) s(1)=

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Advanced Math