there are 6 elementary schools in district. each school has 412 students. how many students in all are in the district? Solve th
1 answer:
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Answer:
a)
b)
c)
d)
cos 330° = 1- 2 sin² (165°)
Step-by-step explanation:
<u><em>Step(i):-</em></u>
By using trigonometry formulas
a)
cos2∝ = 2 cos² ∝-1
cos∝ = 2 cos² ∝/2 -1
1+ cos∝ = 2 cos² ∝/2
b)
cos2∝ = 1- 2 sin² ∝
cos∝ = 1- 2 sin² ∝/2
<u><em>Step(i):-</em></u>
Given
we know that trigonometry formulas
1- cos∝ = 2 sin² ∝/2
Given
put ∝ = 315
multiply with ' 2 sin (∝/2) both numerator and denominator
Apply formulas
1- cos∝ = 2 sin² ∝/2
now we get
b)
put ∝ = 330° above formula
c )
put ∝ = 315° above formula
d)
cos∝ = 1- 2 sin² ∝/2
put ∝ = 330°
cos 330° = 1- 2 sin² (165°)