SOLUTION: how do I solve: f(x)= 4x - 3 g(x)= x^3 + 2x Find (f-g)(4)

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Question 874029: how do I solve:
f(x)= 4x - 3
g(x)= x^3 + 2x
Find (f-g)(4)
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
(f-g)(4) means f(4) - g(4). So we need to calculate f(4) and g(4) first

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f(x) = 4x - 3

f(4) = 4(4) - 3

f(4) = 13

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g(x) = x^3 + 2x

g(4) = (4)^3 + 2(4)

g(4) = 72

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(f-g)(4) = f(4) - g(4)

(f-g)(4) = f(4) - g(4)

(f-g)(4) = 13 - 72

(f-g)(4) = -59

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Final Answer:

(f-g)(4) = -59