Answer:
The magnitude is 
The direction is 
i.e toward the x-axis
Step-by-step explanation:
From the question we are told that
The function is 
The point considered is 
Generally the maximum rate of change of f at the given point and the direction is mathematically represented as
![\Delta f(x,y) = [\frac{\delta f(x,y)}{\delta x } i + \frac{\delta f(x,y)}{\delta y } j ]](https://tex.z-dn.net/?f=%5CDelta%20f%28x%2Cy%29%20%3D%20%20%5B%5Cfrac%7B%5Cdelta%20%20f%28x%2Cy%29%7D%7B%5Cdelta%20x%20%7D%20i%20%2B%20%5Cfrac%7B%5Cdelta%20%20f%28x%2Cy%29%7D%7B%5Cdelta%20y%20%7D%20j%20%20%5D)
![\Delta f(x,y) = [\frac{\delta (9sin(xy))}{\delta x} i + \frac{\delta (9sin(xy))}{\delta y} i ]](https://tex.z-dn.net/?f=%5CDelta%20f%28x%2Cy%29%20%3D%20%20%5B%5Cfrac%7B%5Cdelta%20%20%289sin%28xy%29%29%7D%7B%5Cdelta%20x%7D%20i%20%20%2B%20%5Cfrac%7B%5Cdelta%20%20%289sin%28xy%29%29%7D%7B%5Cdelta%20y%7D%20i%20%20%20%5D)
![\Delta f(x,y) = [9y cos (x,y) i + 9xcos (x,y) j]](https://tex.z-dn.net/?f=%5CDelta%20f%28x%2Cy%29%20%3D%20%5B9y%20cos%20%28x%2Cy%29%20i%20%2B%20%209xcos%20%28x%2Cy%29%20j%5D)
At
![\Delta f (0,8) = [9(8) cos(0* 8)i + 9(8) sin(0* 8)j ]](https://tex.z-dn.net/?f=%5CDelta%20%20f%20%280%2C8%29%20%3D%20%20%5B9%288%29%20cos%280%2A%208%29i%20%20%2B%209%288%29%20sin%280%2A%208%29j%20%20%5D)
a quadrilateral has 4 angles that add up to 360 degrees
x + 80+110+ 75 = 360
combine like terms
x + 265 = 360
subtract 265 from each side
x + 265 -265 =360 -265
x = 95
Choice C
Answer:
The probability that a randomly selected person gets incorrect result is 2.2 × 10⁻⁴
Step-by-step explanation:
The parameters given are;
The accuracy of the test for a person who has the respiratory synctial virus = 97%
The accuracy of the test for a person who does not have the respiratory synctial virus = 99%
We have;
a = TP =
b = FP
c = FN
d = TN
a/(a + c) = 0.97
d/(d + b) = 0.99
a/(a + b) = 0.97*0.0055/(0.97*0.0055 + (1 - 0.99)*(1-0.0055))
PPV = 0.349 = 34.9%
Therefore, we have;
a/(a + c) = 0.97 and
a/(a + b) = 0.349
0.97(a + c) =0.349(a + b)
(0.97 - 0.349)a = 0.349·b - 0.97·c
a = (0.349·b - 0.97·c)0.621
b × (1 - 0.0055) = (1 - 0.97)×(1 - 0.0055)
b = 1 - 0.97 = 0.03
Similarly,
c = 1 - 0.99 = 0.01
The proportion of the population that have false positive and false negative = 0.03 + 0.01 = 0.04 = 4%
The probability that a randomly selected person gets incorrect result = 0.04×0.0055 = 0.00022.
The point lies directly on the regression line.
