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5.
Solve the equation sin tan+cos0=3 for 0° <0 < 360°.

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Explanation:

I assume you mean the equation sin(x)tan(x) + cos(x) = 3.

Let's begin by rearranging the equation:

sin(x)tan(x) = 3 - cos(x)

Now, we can use the identity tan(x) = sin(x) / cos(x) to rewrite the left-hand side:

sin(x) * sin(x) / cos(x) = 3 - cos(x)

sin^2(x) = (3 - cos(x)) * cos(x)

Expanding the right-hand side, we get:

sin^2(x) = 3cos(x) - cos^2(x)

Moving all the terms to the left-hand side, we obtain a quadratic equation in terms of cos(x):

cos^2(x) - 3cos(x) + sin^2(x) = 0

Using the identity sin^2(x) + cos^2(x) = 1, we can substitute sin^2(x) = 1 - cos^2(x) to get:

cos^2(x) - 3cos(x) + 1 = 0

Solving for cos(x) using the quadratic formula, we get:

cos(x) = (3 ± sqrt(5)) / 2

Now, we can use the inverse cosine function to find the corresponding values of x:

x = arccos((3 + sqrt(5)) / 2) ≈ 20.10° or x = arccos((3 - sqrt(5)) / 2) ≈ 159.90°

Therefore, the solutions to the equation sin(x)tan(x) + cos(x) = 3 for 0° < x < 360° are approximately x = 20.10° and x = 159.90°.

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