Let [tex](-5, -3)[/tex] be a point on the terminal side of [tex]\theta[/tex].

Find the exact values of [tex]\sin \theta[/tex], [tex]\sec \theta[/tex], and [tex]\tan \theta[/tex].



Answer :

To find the exact values of [tex]\(\sin \theta\)[/tex], [tex]\(\sec \theta\)[/tex], and [tex]\(\tan \theta\)[/tex] when given the point [tex]\((-5, -3)\)[/tex] on the terminal side of [tex]\(\theta\)[/tex], follow these steps:

1. Calculate the hypotenuse [tex]\( r \)[/tex]:
The hypotenuse [tex]\( r \)[/tex] is found using the Pythagorean theorem, where [tex]\( r \)[/tex] is the distance from the origin to the point [tex]\((-5, -3)\)[/tex].

[tex]\[ r = \sqrt{x^2 + y^2} \][/tex]

Substituting [tex]\( x = -5 \)[/tex] and [tex]\( y = -3 \)[/tex]:

[tex]\[ r = \sqrt{(-5)^2 + (-3)^2} \][/tex]
[tex]\[ r = \sqrt{25 + 9} \][/tex]
[tex]\[ r = \sqrt{34} \][/tex]
Hence,
[tex]\[ r \approx 5.830951894845301 \][/tex]

2. Determine [tex]\(\sin \theta\)[/tex]:
By definition, [tex]\(\sin \theta\)[/tex] is the ratio of the opposite side over the hypotenuse.

[tex]\[ \sin \theta = \frac{y}{r} \][/tex]

Substituting [tex]\( y = -3 \)[/tex] and [tex]\( r \approx 5.830951894845301 \)[/tex]:

[tex]\[ \sin \theta = \frac{-3}{5.830951894845301} \][/tex]
[tex]\[ \sin \theta \approx -0.5144957554275265 \][/tex]

3. Determine [tex]\(\sec \theta\)[/tex]:
By definition, [tex]\(\sec \theta\)[/tex] is the reciprocal of [tex]\(\cos \theta\)[/tex], where [tex]\(\cos \theta\)[/tex] is the ratio of the adjacent side over the hypotenuse.

[tex]\[ \sec \theta = \frac{r}{x} \][/tex]

Substituting [tex]\( r \approx 5.830951894845301 \)[/tex] and [tex]\( x = -5 \)[/tex]:

[tex]\[ \sec \theta = \frac{5.830951894845301}{-5} \][/tex]
[tex]\[ \sec \theta \approx -1.1661903789690602 \][/tex]

4. Determine [tex]\(\tan \theta\)[/tex]:
By definition, [tex]\(\tan \theta\)[/tex] is the ratio of the opposite side over the adjacent side.

[tex]\[ \tan \theta = \frac{y}{x} \][/tex]

Substituting [tex]\( y = -3 \)[/tex] and [tex]\( x = -5 \)[/tex]:

[tex]\[ \tan \theta = \frac{-3}{-5} \][/tex]
[tex]\[ \tan \theta = 0.6 \][/tex]

Therefore, the values are:
[tex]\[ \sin \theta \approx -0.5144957554275265 \][/tex]
[tex]\[ \sec \theta \approx -1.1661903789690602 \][/tex]
[tex]\[ \tan \theta \approx 0.6 \][/tex]