[tex]\cos \theta = \frac{15}{17}[/tex]. Find [tex]\sin \theta[/tex]

A. [tex]\frac{15}{8}[/tex]

B. [tex]\frac{8}{17}[/tex]

C. [tex]\frac{8}{15}[/tex]

D. [tex]\frac{17}{15}[/tex]



Answer :

To find [tex]\(\sin \theta\)[/tex] given that [tex]\(\cos \theta = \frac{15}{17}\)[/tex], we can use the Pythagorean identity:

[tex]\[ \sin^2 \theta + \cos^2 \theta = 1 \][/tex]

Given [tex]\(\cos \theta = \frac{15}{17}\)[/tex], let's denote this value for clarity:

[tex]\[ \cos \theta = \frac{15}{17} \][/tex]

First, let's square [tex]\(\cos \theta\)[/tex]:

[tex]\[ \cos^2 \theta = \left(\frac{15}{17}\right)^2 = \frac{225}{289} \][/tex]

Next, substitute [tex]\(\cos^2 \theta\)[/tex] into the Pythagorean identity:

[tex]\[ \sin^2 \theta + \frac{225}{289} = 1 \][/tex]

Now, solve for [tex]\(\sin^2 \theta\)[/tex]:

[tex]\[ \sin^2 \theta = 1 - \frac{225}{289} \][/tex]

To proceed, we need to subtract [tex]\(\frac{225}{289}\)[/tex] from 1. We can convert 1 to a fraction with the same denominator:

[tex]\[ 1 = \frac{289}{289} \][/tex]

Thus:

[tex]\[ \sin^2 \theta = \frac{289}{289} - \frac{225}{289} = \frac{64}{289} \][/tex]

Now, taking the square root of both sides to find [tex]\(\sin \theta\)[/tex]:

[tex]\[ \sin \theta = \sqrt{\frac{64}{289}} = \frac{\sqrt{64}}{\sqrt{289}} = \frac{8}{17} \][/tex]

Given that [tex]\(\cos \theta\)[/tex] is positive and considering standard trigonometric functions in different quadrants, [tex]\(\sin \theta\)[/tex] should also be positive in this case.

Therefore, the value of [tex]\(\sin \theta\)[/tex] is:

[tex]\[ \boxed{\frac{8}{17}} \][/tex]