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Math Snap
PROBLEM
Find the sum function (f+g)(x) for f(x)=5x+4 if x<2 and x2+4x if x≥2, and g(x)=−3x+1 if x≤0 and g(x)=x−7 if x>0.
STEP 1
Assumptions1. We have two functions, f(x) and g(x), which are defined differently for different ranges of x. . The function f(x) is defined as 5x+4 for x≥ and as x+4x otherwise. 3. The function g(x) is defined as −3x+1 for x≤0 and as x−7 for x>0. 4. We need to find the sum function (f+g)(x).
STEP 2
The sum function (f+g)(x) is defined as f(x)+g(x). Since both f(x) and g(x) are defined differently for different ranges of x, we need to consider these ranges separately.
STEP 3
Let's first consider the range x≤0. In this range, f(x)=x2+x and g(x)=−3x+1. So, the sum function (f+g)(x) is(f+g)(x)=f(x)+g(x)=x2+x+(−3x+1)
STEP 4
implify the expression for (f+g)(x) for x≤0. (f+g)(x)=x2+4x−3x+1=x2+x+1
STEP 5
Next, consider the range 0<x<2. In this range, f(x)=x2+4x and g(x)=x−7. So, the sum function (f+g)(x) is(f+g)(x)=f(x)+g(x)=x2+4x+(x−7)
STEP 6
implify the expression for (f+g)(x) for 0<x<2. (f+g)(x)=x2+4x+x−=x2+5x−
STEP 7
Finally, consider the range x≥2. In this range, f(x)=5x+4 and g(x)=x−7. So, the sum function (f+g)(x) is(f+g)(x)=f(x)+g(x)=5x+4+(x−7)
STEP 8
implify the expression for (f+g)(x) for x≥2. (f+g)(x)=5x+4+x−7=6x−3
SOLUTION
Now we have the sum function (f+g)(x) for all possible ranges of x. So, we can write(f+g)(x)=⎩⎨⎧x2+x+ if x≤x2+5x−7 if <x<26x−3 if x≥2This is the sum function (f+g)(x).