Help me plz I will give 20 point

1) If we have a point (x, y), the angle between the x-axis and a ray that goes from the origin to the point is defined by:

cos(θ) = x/(√(x^2 + y^2))

sin(θ) = y/(√(x^2 + y^2))

Then for the point:

(√(7)/4 , 3/4)

x = √(7)/4

y = 3/4

√(x^2 + y^2) = √((√(7)/4)^2 + ( 3/4)^2) = (1/4)*√(7 + 9) = 1

Then replacing these values in the above equations for the cosine and sine functions, we get:

cos(θ) = x/(√(x^2 + y^2)) = (√(7)/4)/1 = √(7)/4

sin(θ) = y/(√(x^2 + y^2)) = (3/4)/1 = 3/4

2) To find the period, we just need to find the distance between two peaks, or two x-intersects (such that the slope is the same).

Let's look at the graph.

We can see that at x = 0, the graph intersects the x-axis and increases

The next point where this happens is at x = π/3

Then the period of this function is:

P = π/3 - 0 = π/3

The period is π/3

2nd one in the first row is correct

cant open file sorry!

step-by-step explanation: