Respuesta :
Correct question is;
The terminal side of angle θ intersects the unit circle in the first quadrant at (9/25,y). What are the exact values of sinθ and cosθ?
Answer:
sinθ = (√544)/25) and cosθ = 9/25
Step-by-step explanation:
We are given that (9/25,y) lies on the unit circle. Thus, from general representation of equation of a circle, we can write that;
(9/25)² + y² = 1²
y² = 1 - (9/25)²
y² = (625 - 81)/25²
y² = 544/25²
y = ±(√544)/25
We are told the point is in the first quadrant and so we will choose the positive value of y = (√544)/25.
Therefore, the terminal side of the angle θ intersects the unit circle at [9/25, (√544)/25)]
In unit circle geometry, cosθ = x, while sinθ = y.
Thus; sinθ = (√544)/25) and cosθ = 9/25
The exact value of [tex]sin\theta[/tex] and [tex]cos\theta[/tex] is [tex]cos\theta = \frac{9}{25} , sin\theta = \frac{\sqrt{544} }{25}[/tex] and this can be determined by forming the equation of circle.
Given :
The terminal side of angle [tex]\theta[/tex] intersect at unit circle ([tex]\frac{9}{25}, y[/tex]).
From general representation of equation of circle , we can write
[tex]x^{2} + y^{2} = a^{2}\\[/tex]
[tex](\frac{9^{2} }{25^{2} })[/tex] + [tex]y^{2} = 1^{2}[/tex]
[tex]y^{2} = 1 - \frac{81}{625}[/tex]
[tex]y^{2} = \frac{625-81}{625}[/tex]
[tex]y^{2}=\frac{544}{625}[/tex]
Taking square root both sides
[tex]y= \frac{\sqrt{544} }{\sqrt{625} }[/tex]
[tex]y = \frac{\sqrt{544} }{25}[/tex]
We are taking only because point lies in first quadrant.
The terminal side of angel [tex]\theta[/tex] unit circle in first quadrant at [tex](\frac{9}{25} , \frac{\sqrt{544} }{25})[/tex]
In unit circle
[tex]x = cos\theta , y = sin\theta[/tex]
[tex]\rm cos\theta = \frac{9}{25} , sin\theta = \frac{\sqrt{544} }{25}[/tex].
For more information click on the link gives below
https://brainly.com/question/23841023