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3) If f(x)=8-x² and g(x)=x-3, Find the roots of (f+g)(x). Show work

User ADAMJR
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Answer: We can find (f+g)(x) by adding f(x) and g(x):

(f+g)(x) = f(x) + g(x) = (8-x²) + (x-3) = -x² + x + 5

To find the roots of (f+g)(x), we need to set it equal to zero and solve for x:

-x² + x + 5 = 0

We can use the quadratic formula to solve for x:

x = (-b ± sqrt(b² - 4ac)) / 2a

Where a = -1, b = 1, and c = 5:

x = (-1 ± sqrt(1² - 4(-1)(5))) / 2(-1)

x = (-1 ± sqrt(1 + 20)) / -2

x = (-1 ± sqrt(21)) / -2

So the roots of (f+g)(x) are:

x = (-1 + sqrt(21)) / -2

x = (-1 - sqrt(21)) / -2

These roots cannot be simplified any further, so we leave the answer in this form.

Explanation:

User DhrDatt
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