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У20f15(4,12)10g(4,6)(-2,0)(0,25) 2,4,(3,5)(2,0)0,47Use the graph off and g.Find (gof)(2).ما

User Urbushey
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1 Answer

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The first step is to find the fuctions, f(x) and g(x)

Since function f(x) is represented by the curve, it's a quadratic function. The curve cuts the x axis at x = 2 and x = - 2. Thus, the factors are (x + 2) and (x - 2). The quadratic function would be

(x + 2)(x - 2)

= x^2 - 2x + 2x - 4

f(x) = x^2 - 4

Since the function g(x) is represented by a straight line, it is a linear function. We would represent the function in the slope intercept form which is expressed as

y = mx + c

where

m = slope

c = y intercept

To find slope, the formula is

m = (y2 - y1)/(x2 - x1)

From the given points,

when x1 = - 2, y1 = 0

when x2 = 2, y2 = 4

m = (4 - 0)/(2 - - 2) = 4/(2 + 2) = 4/4

m = 1

the y intercept is the value of y when x = 0. Thus, c = 2

The function is

g(x) = x + 2

To find (g o f)(x), we would substitute function f into function g. Thus,

gof(x) = x^2 - 4 + 2

gof(x) = x^2 - 2

To find gof(2), we would substitute x = 2 into gof(x). It becomes

gof(2) = 2^2 - 2 = 4 - 2

gof(2) = 2

User Amandeep Chugh
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