Quick answer I don't think this has an answer.
If you take the cos-1(2 sqrt(2)) your calculator should have a fit. Let's check that out. Mine certainly does. So there is something wrong with the question. If there is something to add in please do it and I will it least put an answer in the comments. As it stands, nothing will work.
If you put your calculator in radians, you will get an answer but it will not be anything resembling the choices you've listed.
If you meant sqrt(2) / 2 that would give 45o. Put it in your calculator like this 2 ^ 0.5 divided by 2 = 0.707
Cos - 1 (0.707) = 45
ANSWER:
36 > 9 > 7 > 0 > -3 > -132
Hope it helps u!
Answer:
D
Step-by-step explanation:
Using the rule of exponents
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Given
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= 
= (
)³
To find the X intercept make y =0. Then factor out a negative on the side with the equation for each of the terms, so it becomes
0=-(x^2+x+3)
0=(x^2+X+3)
0-3=(x^2+X)
-3=x(X+1)
-3=X, X intercept -3,0
-3=(X+1)
-4=X, X intercept -4,0.
These are possible X intercepts you can check by using quadratic formula as well.
Question has missing details (Full question below)
Measurement error that is continuous and uniformly distributed from –3 to +3 millivolts is added to a circuit’s true voltage. Then the measurement is rounded to the nearest millivolt so that it becomes discrete. Suppose that the true voltage is 219 millivolts. What is the mean and variance of the measured voltage
Answer:
Mean = 219
Variance = 4
Step-by-step explanation:
Given
Let X be a random variable measurement error.
X has a discrete uniform distribution as follows
a = 219 - 3 = 216
b = 219 + 3 = 222
Mean or Expected value is calculated as follows;
E(x) = ½(216+222)
E(x) = ½ * 438
E(x) = 219
Variance is calculated as follows;
Var(x) = ((b-a+1)²-1)/12
Var(x) = ((222-216+1)²-1)/12
Var(x) = (7²-1)/12
Var(x) = 48/12
Var(x) = 4