Lines can be used to approximate a wide variety of functions; often a function can be
described using many lines.
If a stock price goes from $10 to $12 from January 1st to January 31, from $12 to $9
from February 1st to February 28th, and from $9 to $15 from March 1st to March 31th
is the price change from $10 to $15 a straight line?
It is clear that in each of the three time intervals mentioned there was a complex daily
variation of prices as in an electrocardiogram. But what would be a simplified solution
for a first naive view of the situation? Would a simple function hold up? What is the
simplest function to represent this situation? Does your naïve initial and simplified
model allow you to predict the behavior of the stock in the next month?
How can I use three “pieces” of lines to describe the price movements from the
beginning of January to the end of March? Show the graph for the price movement.
Go to www.desmos.com/calculator, and write your equations following the example
y=x+2 {0 < x < 2}
y = –x + 6 {2 < x < 5}
y = 2x – 9 {5 < x < 8}
Your Discussion should be a minimum of 250 words in length and not more than 750
words.
, All of these questions can be answered using the formula of a linear equation:
y = mx + b, where m = (y2 - y1) / (x2 - x1)
A table is generated to highlight the date versus the prices of stocks which will be use to identify our 3
pieces of lines.
_x__ _y_
Jan 1 $10
} Line A = yA
Jan 31 $12
______________________________
Feb 1 $12
} Line B = yB
Feb 28 $9
________________________________
Mar 1 $9
} Line C = yC
Mar 31 $15
________________________________
To make our calculation the the x-values will be rename using the number of days versus the date that was
previously used. January 1 will be set at day ‘0’. This is an essential point in the calculations.
_x_ _y_
0 10
} Line A = yA
30 12
______________________________
31 12
} Line B = yB
58 9
______________________________
59 9
} Line C = yC
90 15
______________________________
Calculation of the 3 line pieces:
Line A : y = mx + b using the points (0,10) and (30,12)
mA = (12 - 10) / (30 - 0) = 1/15
=> yA = (1/15) x + b
described using many lines.
If a stock price goes from $10 to $12 from January 1st to January 31, from $12 to $9
from February 1st to February 28th, and from $9 to $15 from March 1st to March 31th
is the price change from $10 to $15 a straight line?
It is clear that in each of the three time intervals mentioned there was a complex daily
variation of prices as in an electrocardiogram. But what would be a simplified solution
for a first naive view of the situation? Would a simple function hold up? What is the
simplest function to represent this situation? Does your naïve initial and simplified
model allow you to predict the behavior of the stock in the next month?
How can I use three “pieces” of lines to describe the price movements from the
beginning of January to the end of March? Show the graph for the price movement.
Go to www.desmos.com/calculator, and write your equations following the example
y=x+2 {0 < x < 2}
y = –x + 6 {2 < x < 5}
y = 2x – 9 {5 < x < 8}
Your Discussion should be a minimum of 250 words in length and not more than 750
words.
, All of these questions can be answered using the formula of a linear equation:
y = mx + b, where m = (y2 - y1) / (x2 - x1)
A table is generated to highlight the date versus the prices of stocks which will be use to identify our 3
pieces of lines.
_x__ _y_
Jan 1 $10
} Line A = yA
Jan 31 $12
______________________________
Feb 1 $12
} Line B = yB
Feb 28 $9
________________________________
Mar 1 $9
} Line C = yC
Mar 31 $15
________________________________
To make our calculation the the x-values will be rename using the number of days versus the date that was
previously used. January 1 will be set at day ‘0’. This is an essential point in the calculations.
_x_ _y_
0 10
} Line A = yA
30 12
______________________________
31 12
} Line B = yB
58 9
______________________________
59 9
} Line C = yC
90 15
______________________________
Calculation of the 3 line pieces:
Line A : y = mx + b using the points (0,10) and (30,12)
mA = (12 - 10) / (30 - 0) = 1/15
=> yA = (1/15) x + b
