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    In maths, do you ever get functions something along the lines of...
    a^b^c^d...etc ?
    just wondered while in a lesson on exponential functions earlier today with e^x^3
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    Yes (although not terribly often).

    See http://en.wikipedia.org/wiki/Tetration
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    (Original post by Toneh)
    In maths, do you ever get functions something along the lines of...
    a^b^c^d...etc ?
    just wondered while in a lesson on exponential functions earlier today with e^x^3
    Yes you do. The question will be something like
    "Find x given that e^x^3=2.73"

    ln e^x^3 = ln 2.73

    x^3= 1.004...

    x = 3√ 1.004...
    x = 1.001...
    x ~ 1.00
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    (Original post by DFranklin)
    Yes (although not terribly often).

    See http://en.wikipedia.org/wiki/Tetration
    aah nice one thanks for that link
    Sometimes I love maths :cool: it can be so ridiculous!
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    (Original post by DFranklin)
    Yes (although not terribly often).

    See http://en.wikipedia.org/wiki/Tetration
    Is tetration not something raised to the power of itself a number of times? E.g. {^4a} = a^{a^{a^a}} and so on. In other words, is a function in the form a^{b^{c^d}} (etc., as in the OP) not just repeated exponentation, in a similar manner to a + b + c + d being repeated addition rather than multiplication (whereas a + a + a + a = 4a).
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    Obviously it's a special case, but it's still a valid example, just as a+a+a+a is a special case of repeated addition (but still a valid example).
 
 
 
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