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NEED HELP ASSIGNMENT DUE IN AN HOUR WOULD BE MUCH APPRECIATED!

NEED HELP ASSIGNMENT DUE IN AN HOUR WOULD BE MUCH APPRECIATED!-example-1
User Khadeeja
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A. To find the inverse of f(x), we need to solve for x in terms of f(x).

Let y = f(x). Then we have:

y = 3/(7x + 1)

Multiplying both sides by 7x + 1, we get:

y(7x + 1) = 3

Expanding the left side, we get:

7xy + y = 3

Subtracting y from both sides, we get:

7xy = 3 - y

Dividing both sides by 7y, we get:

x = (3 - y)/(7y)

Therefore, the inverse of f(x) is:

f^-1(x) = (3 - x)/(7x)

Explanation: To find the inverse function, we set y = f(x) and solve for x. By isolating x on one side of the equation in terms of y, we obtain the inverse function.

B. Let g(x) = (3 - x)/(7x). We need to verify that (f(g(x))) = x for all values of x in the domain of f(x) and g(x).

We have:

f(g(x)) = f((3 - x)/(7x)) = 3/(7((3 - x)/(7x)) + 1) = 3/(3 - x + 7x)/(7x) = 3/(3 + 6x)/(7x) = (21x)/(3 + 6x) = 7x/(1 + 2x)

To show that (f(g(x))) = x, we need to show that:

7x/(1 + 2x) = x

Multiplying both sides by (1 + 2x), we get:

7x = x(1 + 2x)

Expanding the right side, we get:

7x = x + 2x^2

Subtracting 7x from both sides, we get:

0 = x + 2x^2 - 7x

Simplifying, we get:

2x^2 - 6x = 0

Dividing both sides by 2x, we get:

x - 3 = 0

Therefore, x = 3.

Since we have shown that (f(g(x))) = x for x = 3 (which is in the domain of both f(x) and g(x)), we can conclude that g(x) is the inverse of f(x).

C. We cannot answer part C of the question because no function is given. The table provided only shows a set of input-output pairs, but we need the function itself to perform any further analysis.

The domain and range of the inverse function f^-1(x) = (3 - x)/(7x) depend on the domain and range of the original function f(x) = 3/(7x + 1).

The domain of f(x) is all real numbers except -1/7 (since division by zero is undefined). Therefore, the range of f^-1(x) is all real numbers except 0, since division by zero is also undefined.

To find the domain of f^-1(x), we can consider the denominator of the expression for f^-1(x), which is 7x. Since division by zero is undefined, we need to exclude any value of x that makes the denominator equal to zero. Therefore, the domain of f^-1(x) is all real numbers except 0.

In summary:

Domain of f^-1(x): All real numbers except 0
Range of f^-1(x): All real numbers except 0
User Chad Johnson
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