Answer:
x = π/4 and 5π/4
Step-by-step explanation:
Given the expression;
2cos²x - 1 = 0
2cos²x = 0+1
2cos²x = 1
cos²x = 1/2
cos x = ±√1/2
cos x = ±0.7071
x = arccos(±0.7071)
x = ±45 degrees
Convert to radians
Sence 180° = π rad
45° = x
x = 45π/180
x = π/4
If x = -45°
Since cos is negative in the 3rd quadrant
x = 180 + 45
x = 225°
x = 225π/180
x = 45π/36
x = 5π/4
Answer:
the answer is A
Step-by-step explanation:
i said a because
5×5=25
6×5=30
8×5=40
Answer:
x = 14
Step-by-step explanation:
x- 9 = 5
Note the equal sign, what you do to one side, you do to the other. Isolate the variable, x. Add 9 to both sides of the equation:
x - 9 (+9) = 5 (+9)
x = 5 + 9
x = 14
x = 14 is your answer.
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Answer:
For this case we can use the probability mass function and we got:

Step-by-step explanation:
Previous concepts
A Bernoulli trial is "a random experiment with exactly two possible outcomes, "success" and "failure", in which the probability of success is the same every time the experiment is conducted". And this experiment is a particular case of the binomial experiment.
The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".
The probability mass function for the Binomial distribution is given as:
Where (nCx) means combinatory and it's given by this formula:
Solution to the problem
Let X the random variable of interest, on this case we now that:
For this case we can use the probability mass function and we got:

Answer:
look at the photo i have sent