Find sin(2x), cos(2x), and tan(2x) from the given information. csc(x) = 4, tan(x) < 0 sin (2x) = cos(2x) = tan(2x) =

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## Trigonometric Identities and Solutions

Given the following information:

\[ \csc(x) = 4 \]

\[ \tan(x) < 0 \]

We are to find \(\sin(2x)\), \(\cos(2x)\), and \(\tan(2x)\).

### Solution

First, use the given information:

Since \(\csc(x) = \frac{1}{\sin(x)}\), we can find \(\sin(x)\):

\[ \sin(x) = \frac{1}{\csc(x)} = \frac{1}{4} \]

Next, we need \(\cos(x)\). We use the Pythagorean identity:

\[ \sin^2(x) + \cos^2(x) = 1 \]

Substitute \(\sin(x) = \frac{1}{4}\):

\[ \left(\frac{1}{4}\right)^2 + \cos^2(x) = 1 \]

\[ \frac{1}{16} + \cos^2(x) = 1 \]

\[ \cos^2(x) = 1 - \frac{1}{16} = \frac{15}{16} \]

Since \(\tan(x) < 0\), \(\cos(x)\) must be negative:

\[ \cos(x) = -\sqrt{\frac{15}{16}} = -\frac{\sqrt{15}}{4} \]

Now, we find the values of the trigonometric identities for \(2x\):

### \(\sin(2x)\)
We use the double-angle formula:

\[ \sin(2x) = 2 \sin(x) \cos(x) \]

\[ \sin(2x) = 2 \left(\frac{1}{4}\right) \left(-\frac{\sqrt{15}}{4}\right) = 2 \left(-\frac{\sqrt{15}}{16}\right) = -\frac{\sqrt{15}}{8} \]

### \(\cos(2x)\)
We use the double-angle formula:

\[ \cos(2x) = \cos^2(x) - \sin^2(x) \]

\[ \cos(2x) = \left(-\frac{\sqrt{15}}{4}\right)^2 - \left(\frac{1}{4
Transcribed Image Text:## Trigonometric Identities and Solutions Given the following information: \[ \csc(x) = 4 \] \[ \tan(x) < 0 \] We are to find \(\sin(2x)\), \(\cos(2x)\), and \(\tan(2x)\). ### Solution First, use the given information: Since \(\csc(x) = \frac{1}{\sin(x)}\), we can find \(\sin(x)\): \[ \sin(x) = \frac{1}{\csc(x)} = \frac{1}{4} \] Next, we need \(\cos(x)\). We use the Pythagorean identity: \[ \sin^2(x) + \cos^2(x) = 1 \] Substitute \(\sin(x) = \frac{1}{4}\): \[ \left(\frac{1}{4}\right)^2 + \cos^2(x) = 1 \] \[ \frac{1}{16} + \cos^2(x) = 1 \] \[ \cos^2(x) = 1 - \frac{1}{16} = \frac{15}{16} \] Since \(\tan(x) < 0\), \(\cos(x)\) must be negative: \[ \cos(x) = -\sqrt{\frac{15}{16}} = -\frac{\sqrt{15}}{4} \] Now, we find the values of the trigonometric identities for \(2x\): ### \(\sin(2x)\) We use the double-angle formula: \[ \sin(2x) = 2 \sin(x) \cos(x) \] \[ \sin(2x) = 2 \left(\frac{1}{4}\right) \left(-\frac{\sqrt{15}}{4}\right) = 2 \left(-\frac{\sqrt{15}}{16}\right) = -\frac{\sqrt{15}}{8} \] ### \(\cos(2x)\) We use the double-angle formula: \[ \cos(2x) = \cos^2(x) - \sin^2(x) \] \[ \cos(2x) = \left(-\frac{\sqrt{15}}{4}\right)^2 - \left(\frac{1}{4
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