Given f(x) = the quantity of x minus 5, divided by 3, solve for f-1(3).
Solution:
Given, f(x) = the quantity of x minus 5,divided by 3
We have to find f-1(3).
The function can be written as f(x) = (x - 5) / 3
First replace f(x) with y.
y = (x - 5) / 3
Using the multiplicative distributive property
3y = x - 5
Next replace x with y and y with x.
3x = y - 5
y = 3x + 5
Finally replace y with f-1 (x).
f-1 (x) = 3x + 5
Put x = 4 in the above function,
f-1(3) = 3(3) + 5
= 9 + 5
= 14
Verification:
(f ∘ f -1) (x) = x
(f ∘ f -1) (x)= f [ f-1 (x)]
= f [3x + 5]
= 1/3[(3x + 5) -5]
= 1/3(3x - 0)
= 3x/3
= x
Therefore, f-1(3) = 14.
Given f(x) = the quantity of x minus 5, divided by 3, solve for f-1(3).
Summary:
Given f(x) = the quantity of x minus 5, divided by 3, then f-1(3) is 14.
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