121 t-shirts comes to about $3,020
Part A
Answer: The common ratio is -2
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Explanation:
To get the common ratio r, we divide any term by the previous one
One example:
r = common ratio
r = (second term)/(first term)
r = (-2)/(1)
r = -2
Another example:
r = common ratio
r = (third term)/(second term)
r = (4)/(-2)
r = -2
and we get the same common ratio every time
Side Note: each term is multiplied by -2 to get the next term
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Part B
Answer:
The rule for the sequence is
a(n) = (-2)^(n-1)
where n starts at n = 1
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Explanation:
Recall that any geometric sequence has the nth term
a(n) = a*(r)^(n-1)
where the 'a' on the right side is the first term and r is the common ratio
The first term given to use is a = 1 and the common ratio found in part A above was r = -2
So,
a(n) = a*(r)^(n-1)
a(n) = 1*(-2)^(n-1)
a(n) = (-2)^(n-1)
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Part C
Answer: The next three terms are 16, -32, 64
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Explanation:
We can simply multiply each previous term by -2 to get the next term. Do this three times to generate the next three terms
-8*(-2) = 16
16*(-2) = -32
-32*(-2) = 64
showing that the next three terms are 16, -32, and 64
An alternative is to use the formula found in part B
Plug in n = 5 to find the fifth term
a(n) = (-2)^(n-1)
a(5) = (-2)^(5-1)
a(5) = (-2)^(4)
a(5) = 16 .... which matches with what we got earlier
Then plug in n = 6
a(n) = (-2)^(n-1)
a(6) = (-2)^(6-1)
a(6) = (-2)^(5)
a(6) = -32 .... which matches with what we got earlier
Then plug in n = 7
a(n) = (-2)^(n-1)
a(7) = (-2)^(7-1)
a(7) = (-2)^(6)
a(7) = 64 .... which matches with what we got earlier
while the second method takes a bit more work, its handy for when you want to find terms beyond the given sequence (eg: the 28th term)
Step-by-step explanation:
System of Linear Equations entered :
[1] 2x-y=4 [2] y-x=4
Equations Simplified or Rearranged :
[1] 2x - y = 4 [2] -x + y = 4
Graphic Representation of the Equations :
y + 2x = 4 y - x = 4
Solve by Substitution :
// Solve equation [2] for the variable y
[2] y = x + 4
// Plug this in for variable y in equation [1]
[1] 2x - (x +4) = 4 [1] x = 8
// Solve equation [1] for the variable x
[1] x = 8
// By now we know this much :
x = 8 y = x+4
// Use the x value to solve for y
y = (8)+4 = 12
Solution :
{x,y} = {8,12}
Answer: 63.7 + (-26) = 37.7
Answer:
The magnitude of the necessary lifting force is 7.95N
Step-by-step explanation:
Force = mv^2/r
mass (m) = 2.00105kg, velocity (v) = 123m/s, radius (r) = 3810m
Force = 2.00105×123^2/3810 = 30273.89/3810 = 7.95N
