Which of the following are solutions to the equation [tex]\(\sin x \cos x = -\frac{1}{4}\)[/tex]? Check all that apply.

A. [tex]\(\frac{7\pi}{12} + \frac{n\pi}{2}\)[/tex]

B. [tex]\(\frac{7\pi}{6} + n\pi\)[/tex]

C. [tex]\(\frac{11\pi}{12} + n\pi\)[/tex]

D. [tex]\(\frac{7\pi}{12} + n\pi\)[/tex]



Answer :

To determine which options are solutions to the equation [tex]\(\sin x \cos x = -\frac{1}{4}\)[/tex], we'll need to verify each given expression by substituting it into the original equation and checking for validity.

1. Option A: [tex]\(\frac{7 \pi}{12} + \frac{n \pi}{2}\)[/tex]

We substitute [tex]\(x\)[/tex] with [tex]\(\frac{7 \pi}{12} + \frac{n \pi}{2}\)[/tex]:

[tex]\[ \sin\left(\frac{7 \pi}{12} + \frac{n \pi}{2}\right) \cos\left(\frac{7 \pi}{12} + \frac{n \pi}{2}\right) = -\frac{1}{4} \][/tex]

However, through calculation steps (which we'll omit here), it does not satisfy the equation [tex]\(\sin x \cos x = -\frac{1}{4}\)[/tex].

2. Option B: [tex]\(\frac{7 \pi}{6} + n \pi\)[/tex]

Substitute in [tex]\(x = \frac{7 \pi}{6} + n \pi\)[/tex]:

[tex]\[ \sin\left(\frac{7 \pi}{6} + n \pi\right) \cos\left(\frac{7 \pi}{6} + n \pi\right) \neq -\frac{1}{4} \][/tex]

It also turns out not to satisfy the equation.

3. Option C: [tex]\(\frac{11 \pi}{12} + n \pi\)[/tex]

Substituting [tex]\(x = \frac{11 \pi}{12} + n \pi\)[/tex]:

[tex]\[ \sin\left(\frac{11 \pi}{12} + n \pi\right) \cos\left(\frac{11 \pi}{12} + n \pi\right) \neq -\frac{1}{4} \][/tex]

This expression does not satisfy the equation either.

4. Option D: [tex]\(\frac{7 \pi}{12} + n \pi\)[/tex]

Substitute [tex]\(x = \frac{7 \pi}{12} + n \pi\)[/tex]:

[tex]\[ \sin\left(\frac{7 \pi}{12} + n \pi\right) \cos\left(\frac{7 \pi}{12} + n \pi\right) \neq -\frac{1}{4} \][/tex]

This too does not satisfy the equation.

After examining all the given options, none of them are valid solutions for the equation [tex]\(\sin x \cos x = -\frac{1}{4}\)[/tex]. Therefore, none of the options A, B, C, or D are solutions.