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    f : x I-> 2x – 1
    g : x I-> , x ≠ 0

    (a) Find the value of
    (i) f(3),
    ...............................
    (ii) fg(6).
    ...............................
    (b) Express the inverse function f –1 in the form f –1: x ...
    .............................
    (c) (i) Express the composite function gf in the form gf : x ...
    ...............................
    (ii) Which value of x must be excluded from the domain of gf ?
    x = ........................
    (2)

    How do I go about this? (the box represents a symbol I-> )

    not the first two
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    Well, what have you done yourself?
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    I can understand the first two, but I am confused with the symbol I->. Does it mean the same thing as an equals sign?

    I can do the exclusion one provided I can do the others. We have always used = rather than I->
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    It roughly means "maps to". For example, f : x \to 2x-1 means that the function f takes a value x and outputs a value of (2x-1). An alternative notation for this is f(x) = 2x-1
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    Thanks! Ill relay back the answer and it would be great if you could check it!
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    ok here goes:

    a) 5
    ii) 0
    b) (x+1)/2
    c) 3/(2x-1)
    ii) 1/2
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    Well, you haven't told us what g is, but your answers to a)i. and b) are correct.
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    what do you mean?
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    In your first post, you haven't told us what the function g is. This, combined with my lack of supernatural powers, means I cannot check the rest of your answers.
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    oh i am extremely sorry

    g(x)= 3/x (and cannot equal 0 for obvious reasons)
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    Your answers look right
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    thanks very much
 
 
 
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Updated: November 13, 2008
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