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# A^b^c^d... whut? watch

1. 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
2. Yes (although not terribly often).

See http://en.wikipedia.org/wiki/Tetration
3. (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
4. (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 it can be so ridiculous!
5. (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. and so on. In other words, is a function in the form (etc., as in the OP) not just repeated exponentation, in a similar manner to being repeated addition rather than multiplication (whereas ).
6. 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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