Answer:
a) Mean, E(X) = - 0.5
Variance = = 9.25
b) 
or
⇒ 
⇒ 
Step-by-step explanation:
Given:
moment generating function of X as:
MX(t) = 
a) Now
Mean, E(X) =
Thus,

or

also,
Thus,

or

Therefore,
Mean, E(X) = 
or
Mean, E(X) = - 0.5
and

or
= 9.5
also,
Variance(X) = E(X²) - E(X)²
⇒ 9.5 - (-0.5)²
= 9.25
b) Now,
Let f(x) be the PMF of X
Thus,

or
⇒ 
⇒ 
Therefore,
at x = 0, P(x) =
at x= - 4 ,P(x) = 
at x = 5, P(x) =
Thus,
E(X) =
or
E(X) = - 0.5
also,
= 9.5
Hence,
Var(X) = E(X²) - E(X)²
⇒ 9.5 - (-0.5)²
= 9.25
Answer:
B
Step-by-step explanation:
f(x) = x²+49 , rewrite the equation
x² +7² =0 , to find the roots make f(x) =0 and subtract 7² from both sides
x² = -7², square root both sides
√x² =√-7², consider √-1 =i
x= ±7i
the roots are -7i and 7i
Answer:
b=12, y=53.13°, and x=36.87° brainliest pls if correct
C) Adjacent angles whose exterior sides are perpendicular rays are complementary.
Complementary = add up to 90
Supplementary = add up to 180
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