It would be 5 because 5+4=9 and 9>8 (9 is greater than 8)
The answer is B. Would you like an explanation why?
The cosine of an angle is the x-coordinate of the point where its terminal ray intersects the unit circle. So, we can draw a line at x=-1/2 and see where it intersects the unit circle. That will tell us possible values of θ/2.
We find that vertical line intersects the unit circle at points where the rays make an angle of ±120° with the positive x-axis. If you consider only positive angles, these angles are 120° = 2π/3 radians, or 240° = 4π/3 radians. Since these are values of θ/2, the corresponding values of θ are double these values.
a) The cosine values repeat every 2π, so the general form of the smallest angle will be
... θ = 2(2π/3 + 2kπ) = 4π/3 + 4kπ
b) Similarly, the values repeat for the larger angle every 2π, so the general form of that is
... θ = 2(4π/3 + 2kπ) = 8π/3 + 4kπ
c) Using these expressions with k=0, 1, 2, we get
... θ = {4π/3, 8π/3, 16π/3, 20π/3, 28π/3, 32π/3}
The numbers that can be expressed in the form of a fraction are called rational numbers. While that numbers that cannot be expressed in the form of a fraction are called irrational numbers.


is an irrational number, it cannot be expressed in the form of a fraction.
Answer:
Formula: a² + 2ab + b² = (a + b)²
The square root of 1/9x² = 1/3x so a = 1/3x and b = 1/5y.
The answer is (1/3x + 1/5y)².