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    The function f is defined by f : x → 3 + ln (x + 2), x ∈ R , x ≥ k, where k is a constant. Given that the range of f is f(x) ≥ 3,

    a) find the value of k,

    b) find f −1(x), stating its domain clearly.

    Can someone tell me if I have answered this question correctly?

    For part a), I drew a graph of the function and worked out that when y=3, x=-1, therefore the domain must be x ≥ -1, therefore k = -1.

    For part b) I worked out that the inverse function is ex-3 -2 which I am not sure is correct.
    I don't know how to find the domain for this though... How do you do it?:confused:
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    (Original post by jessyjellytot14)
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    Domain of the inverse is the range of the original. Remember what happens with y and x when it comes to the inverse, apply the same idea to the constraints.
 
 
 
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