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}
If the apple is on the ground, then the height y is 0. To find t, just plug in 0 for y:




So the answer is 2.74 seconds.
Note that taking the square root of 7.5, mathematically, gives you both 2.74 and -2.74. But because we know that time did not go backwards, only the positive value for t was considered.
Answer:
1.6 hours
Step-by-step explanation:
Number of opening hours a day = 8
Number of groups = 5
Dividing the number of opening. Hours equally among the 5 groups :
8 hours / 5
= 1.6 hours per group per day
2 by 7 + – is equals to 1 so we can say that x.
x=1-2/7
x=7/7-2/7
x=5/7
Solve your equation step-by-step.
x^2+5=41
Subtract 5 from both sides.
x^2+5−5=41−5
x^2=36
Take square root.
x=±√36
x=6
or
x=−6
So your answer suppose to be C and D.
But if you were to put only one answer in the answering box, then just say C)