How do exponents raised to another exponent work?

1 Answer
Mar 29, 2016

See explanation...

Explanation:

One way of visualising basic positive integer exponents is as repeated multiplication:

a^n = overbrace(a xx a xx .. xx a)^"n times"

Then we find:

a^m xx a^n = overbrace(a xx a xx .. xx a)^"m times" xx overbrace(a xx a xx .. xx a)^"n times"

=overbrace(a xx a xx .. xx a)^"m + n times" = a^(m+n)

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The next level of complexity is when a value that has been raised to an exponent is raised to another exponent:

(a^b)^c = a^(bc)

For example, (2^2)^3 = 4^3 = 64

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The next level is where a value is raised to a value that has been raised to an exponent:

Note that a^(b^c) is evaluated from right to left, not left to right.

So:

a^(b^c) = a^((b^c))

For example, 2^(2^3) = 2^8 = 256