I do not understand how to answer this question: f(x) = 1 x + 2 a) find the value of x which must be excluded from the domain of f(x) b) find the inverse function f-1 (x) Help would be appreciated on either question
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Originally Posted by abbie1212 I do not understand how to answer this question: f(x) = 1 x + 2 a) find the value of x which must be excluded from the domain of f(x) b) find the inverse function f-1 (x) Help would be appreciated on either question a) The term of the function is a fraction. Keep in mind that the division by zero is not allowed. b) Take the equation y = f(x). That means $\displaystyle y=\frac1{x+2}$ Now swap the variables x and y and solve for y again.
Dear abbie1212, I assume you have written, f(x)=1/(x+2) Now you could see that this function does not have a value when x=-2. (f(x)would be infinite.) Therefore x=-2 must be excluded from the domain of f.
Thanks, but still a bit confused, what is the answer and how?
Originally Posted by abbie1212 Thanks, but still a bit confused, what is the answer and how? what answer? the question about the function's domain or its inverse?
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