Answer:
A. E(x) = 1/n×n(n+1)/2
B. E(x²) = 1/n
Step-by-step explanation:
The n candidates for a job have been ranked 1,2,3....n. Let x be the rank of a randomly selected candidate. Therefore, the PMF of X is given as
P(x) = {1/n, x = 1,2...n}
Therefore,
Expectation of X
E(x) = summation {xP(×)}
= summation {X×1/n}
= 1/n summation{x}
= 1/n×n(n+1)/2
= n+1/2
Thus, E(x) = 1/n×n(n+1)/2
Value of E(x²)
E(x²) = summation {x²P(×)}
= summation{x²×1/n}
= 1/n
cot(<em>θ</em>) = cos(<em>θ</em>)/sin(<em>θ</em>)
So if both cot(<em>θ</em>) and cos(<em>θ</em>) are negative, that means sin(<em>θ</em>) must be positive.
Recall that
cot²(<em>θ</em>) + 1 = csc²(<em>θ</em>) = 1/sin²(<em>θ</em>)
so that
sin²(<em>θ</em>) = 1/(cot²(<em>θ</em>) + 1)
sin(<em>θ</em>) = 1 / √(cot²(<em>θ</em>) + 1)
Plug in cot(<em>θ</em>) = -2 and solve for sin(<em>θ</em>) :
sin(<em>θ</em>) = 1 / √((-2)² + 1)
sin(<em>θ</em>) = 1/√(5)
The value of constant c for which the function k(x) is continuous is zero.
<h3>What is the limit of a function?</h3>
The limit of a function at a point k in its field is the value that the function approaches as its parameter approaches k.
To determine the value of constant c for which the function of k(x) is continuous, we take the limit of the parameter as follows:


Provided that:

Using l'Hospital's rule:

Therefore:

Hence; c = 0
Learn more about the limit of a function x here:
brainly.com/question/8131777
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Answer:
75 times.
Step-by-step explanation:
Well there are 12 months and 3 of them start with the letter J, so theoretically, 25% of the months chosen will start with the letter J because
, which is 25%. 25% of 300 (or
, for those who like fractions) is 75, so theoretically, we can expect a month that starts with the letter J 75 times.
Hope this helps!
<em>P.S: </em><u><em>Please mark me as brainliest!</em></u>