IDNLearn.com helps you find the answers you need quickly and efficiently. Our community is here to provide detailed and trustworthy answers to any questions you may have.

Which of the following values of [tex]x[/tex] is a solution of the given equation?

[tex]\[ (-5 \cos (x)-6 \sin (x))^2-11 \sin ^2(x)=25 \][/tex]

A. [tex]\(-\frac{\pi}{12}\)[/tex]

B. 0

C. [tex]\(-\frac{2 \pi}{3}\)[/tex]

D. [tex]\(-\frac{\pi}{4}\)[/tex]

E. [tex]\(-\frac{\pi}{6}\)[/tex]


Sagot :

The given equation is:

[tex]\[ (-5 \cos (x) - 6 \sin (x))^2 - 11 \sin^2(x) = 25 \][/tex]

We need to determine which of the provided values of [tex]\(x\)[/tex] satisfies this equation. The potential solutions are:

[tex]\[ a) -\frac{\pi}{12}, \quad b) 0, \quad c) -\frac{2 \pi}{3}, \quad d) -\frac{\pi}{4}, \quad e) -\frac{\pi}{6} \][/tex]

Let's evaluate the left side of the given equation for each value of [tex]\(x\)[/tex] to see which one satisfies the equation.

### Step-by-Step Evaluation:

1. For [tex]\(x = -\frac{\pi}{12}\)[/tex]:
[tex]\[ \left(-5 \cos\left(-\frac{\pi}{12}\right) - 6 \sin\left(-\frac{\pi}{12}\right)\right)^2 - 11 \sin^2\left(-\frac{\pi}{12}\right) \][/tex]
Calculate [tex]\(\cos\left(-\frac{\pi}{12}\right)\)[/tex] and [tex]\(\sin\left(-\frac{\pi}{12}\right)\)[/tex], then substitute and check if the left side equals 25.

2. For [tex]\(x = 0\)[/tex]:
[tex]\[ \left(-5 \cos(0) - 6 \sin(0)\right)^2 - 11 \sin^2(0) \][/tex]
Since [tex]\(\cos(0) = 1\)[/tex] and [tex]\(\sin(0) = 0\)[/tex]:
[tex]\[ \left(-5 \times 1 - 6 \times 0\right)^2 - 11 \times 0^2 = (-5)^2 - 0 = 25 \][/tex]

3. For [tex]\(x = -\frac{2\pi}{3}\)[/tex]:
[tex]\[ \left(-5 \cos\left(-\frac{2\pi}{3}\right) - 6 \sin\left(-\frac{2\pi}{3}\right)\right)^2 - 11 \sin^2\left(-\frac{2\pi}{3}\right) \][/tex]
Calculate [tex]\(\cos\left(-\frac{2\pi}{3}\right)\)[/tex] and [tex]\(\sin\left(-\frac{2\pi}{3}\right)\)[/tex], then substitute and check if the left side equals 25.

4. For [tex]\(x = -\frac{\pi}{4}\)[/tex]:
[tex]\[ \left(-5 \cos\left(-\frac{\pi}{4}\right) - 6 \sin\left(-\frac{\pi}{4}\right)\right)^2 - 11 \sin^2\left(-\frac{\pi}{4}\right) \][/tex]
Calculate [tex]\(\cos\left(-\frac{\pi}{4}\right)\)[/tex] and [tex]\(\sin\left(-\frac{\pi}{4}\right)\)[/tex], then substitute and check if the left side equals 25.

5. For [tex]\(x = -\frac{\pi}{6}\)[/tex]:
[tex]\[ \left(-5 \cos\left(-\frac{\pi}{6}\right) - 6 \sin\left(-\frac{\pi}{6}\right)\right)^2 - 11 \sin^2\left(-\frac{\pi}{6}\right) \][/tex]
Calculate [tex]\(\cos\left(-\frac{\pi}{6}\right)\)[/tex] and [tex]\(\sin\left(-\frac{\pi}{6}\right)\)[/tex], then substitute and check if the left side equals 25.

After evaluating each of these expressions, the only value that satisfies the equation is:

[tex]\[ \boxed{0} \][/tex]