The roots of 2x^2-3x=4 are a and b. Find the simplest quadratic equation which has roots 1/a and 1/b
1 answer:
Find the roots
solve
we use hmm, completing the suare
2(x²-1.5x)=4
divide both sides by 2
x²-1.5x=2
take 1/2 of linear coeiftn and square it
-1.5/2=-0.75, (-0.75)²=0.5625
add that to both sides
x²-1.5x+0.5625=2+0.5625
factor perfect squaer trinomial
(x-0.75)²=2.5625
square root both sides, remember to take positive and negative square roots
x-0.75=+/-√2.5625
add 0.75 to both sides
x=0.75+/-√2.5625
the roots are x=0.75+√2.5625 and x=0.75-√2.5625
1/a and 1/b
1/(0.75+√2.5625) and 1/(0.75-√2.5625)
if the roots of a quadratic equation are r1 and r2 then it factors to
(x-r1)(x-r2)
so then we can factor our equation to be
if we were to try and expand it, we would get
x²+0.75x-0.5
that's the simpliest equation with roots 1/a and 1/b where a and b are he roots of 2x²-3x=4
x²+0.75x-0.5 is answer
solve
we use hmm, completing the suare
2(x²-1.5x)=4
divide both sides by 2
x²-1.5x=2
take 1/2 of linear coeiftn and square it
-1.5/2=-0.75, (-0.75)²=0.5625
add that to both sides
x²-1.5x+0.5625=2+0.5625
factor perfect squaer trinomial
(x-0.75)²=2.5625
square root both sides, remember to take positive and negative square roots
x-0.75=+/-√2.5625
add 0.75 to both sides
x=0.75+/-√2.5625
the roots are x=0.75+√2.5625 and x=0.75-√2.5625
1/a and 1/b
1/(0.75+√2.5625) and 1/(0.75-√2.5625)
if the roots of a quadratic equation are r1 and r2 then it factors to
(x-r1)(x-r2)
so then we can factor our equation to be
if we were to try and expand it, we would get
x²+0.75x-0.5
that's the simpliest equation with roots 1/a and 1/b where a and b are he roots of 2x²-3x=4
x²+0.75x-0.5 is answer
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Answer:
- The answer or forecast for temperature using a three-day moving average =
- The answer or forecast for temperature using a three-day moving average =
- The mean absolute deviation based on a two-day moving average, covering all days =
Step-by-step explanation:
1. Three-point averages are calculated by taking a number in the series with the previous and next numbers and averaging the three of them.
Step I - Calculate the three series of succession of numbers form the data and find the average of each of them:
A) (90 + 93 +90)/3 = 91.00
B) (93 + 92 + 90)/3 = 91.67
C) (90 + 92 +90)/3 = 90.67
D) (92 + 90 + 88)/3 = 90.00
E) (90 + 88 + 98)/3 = 92.00
So our series approximated to the nearest whole number is:
91, 92, 91, 90, 92
STEP II
From the series above the highest temperature today is unpredictable because the series is irregular. It went from 91 to 92, then it dropped to 90 and came back to 92.
2. Using a two day moving average we have
STEP I .
Calculate the moving averages
A) (90+93)/2 = 91.50
B) (93 + 90)/2 = 91.50
C) (90 + 92)/2 = 91.00
D) (92 +90)/2 = 91.00
E) (90 + 88)/2 = 89.00
F) (88 + 98)/2 = 93.00
STEP II
The temperature also cannot be predicted because of the irregular series.
3. Calculating the Mean Absolute Deviation based on a two-day moving average
The formula for MAD = (∑||)/
STEP I
To find the mean absolute deviation of the data, start by finding the mean of the data set.
Mean of the data set =
(91.50 + 91.50 + 91.00 + 91.00 + 89.00 +93.00)/6
Mean = 91.17
STEP II
Get the distance between the data point and the mean:
- 91.50-91.17=0.33
- 91.50-91.17= 0.33
- 91.00-91.17= -0.17
- 91.00-91.17= -0.17
- 89.00-91.17= -2.17
- 90.00-91.17= -1.17
STEP II
Add all the distances together
0.33 + 0.33 - 0.17 - 0.17 - 2.17 - 1.17 = -3.02
STEP III
Divide the the sum by data points
-3.02/6
= -0.50
So on average the temperatures were <em>-0.50</em> from the mean.
Cheers!