Answer:
Step-by-step explanation:
So explicit formula essentially is general term formula. Or a formula that when you put in a value for n, you can get that number term in the arithmetic sequence. The way this formula is written is:
![u_{n} = u_{1} + (n-1)d](https://tex.z-dn.net/?f=u_%7Bn%7D%20%3D%20u_%7B1%7D%20%2B%20%28n-1%29d)
Where
is the term (result of this formula) that is based on whatever value you put in for n
is the first term of the sequence
n is the term number that you want
and d is the common difference
So to fill in a general formula or explicit formula all we need is
and d, because this gives us a general expression for any term we choose, or for any value of n
So to find d, all we have to do is take the difference between a term in front and a term behind that term. Ill show you what I mean:
So if we consider the sequence above we can do
-3 - 3 or -9 - (-3) or 15 - (-9) or -21 -(-15) all of these will give us the value for d (we just take a term before and subtract it by the term after)
So all of these come out to a value of -6
So d = -6
is just our first term so:
= 3
Therefore, our explicit formula is
![u_{n} = 3 + (n-1)(-6)](https://tex.z-dn.net/?f=u_%7Bn%7D%20%3D%203%20%2B%20%28n-1%29%28-6%29)
Answer: 0.4 which is choice C
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Work Shown
Focus on the "riverside high school" row only
A = number of twelfth graders = 200
B = number of students = 500
P = probability of picking a twelfth grader
P = A/B
P = 200/500
P = 2/5
P = 0.4
Answer:
V = 5 m/h
Step-by-step explanation:
An aircraft carrier, traveled 9 hours at speed of 25 mph, that means the aircraft position from Hawaii (the start point of the journey) is:
25 m/h * 9 h = 225 miles far away from hawaii
When the aircraft has traveled 9 hours, the submarine has traveled 11 hours ( since its departure was 2 hours earlier ). They both traveled in opposite directions.
Then distance between the two vessels = d
d = 280 miles
280 = 225 miles (from the aircraft to hawaii ) + traveled distance for the submarine
And
Traveled distance by submarine d(s) = V* 11 miles/hour. where V is speed of submarine
Then
280 = 225 + 11*V ⇒ 11*V = 280-225 ⇒ 11*V = 55/11 mph
V = 5 m/h
Answer:
nice I just got this fact rn I didn't know it.. Thank you
To simplify 2x+3-x+5, we can first group x together,then calculate:
![2x + 3 - x + 5 \\ = 2x - x + 3 - 5 \\ = x - 2](https://tex.z-dn.net/?f=2x%20%2B%203%20-%20x%20%2B%205%20%5C%5C%20%20%3D%202x%20-%20x%20%2B%203%20-%205%20%5C%5C%20%20%3D%20x%20-%202)
Therefore the answer is x-2.
Hope it helps!