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°)

is differentiable across its domain, so the MVT says there is some value of

in the open interval

such that

You have

so the equation above becomes

Solve for

.




so

is indeed the average of the endpoints, i.e. the midpoint.
Answer:
79.77%
Step-by-step explanation:
P(X≥120) = normalcdf(120,1e99,130,12) = 0.7976716754 ≈ 0.7977 = 79.77%
Therefore, about 79.77% of operations last at least 120 minutes
45+10x the x stands for how many classes you take
Top one is x+3, bottom one is 5