This has been asked a bunch before so I’m repeating this explanation from u/AxolotlsAreDangerous
x^5 / x^3 = (x* x* x* x* x)/(x* x* x)
=x^2
In general, x^n /x^m = xn-m
Let m=n, this property should still hold.
x^n /x^n =x^n-n =x^0
Any number divided by itself is 1, x0 =1.
1 is, in a sense, to multiplication what 0 is to addition. They’re the identity element , meaning x* 1=x and x+0=x.
Powers are repeated multiplication.
So 2^1 = 2
2^2 = 2×2 = 4
2^3 = 2x2x2 = 8
2^4 = 2x2x2x2 = 16
If you look at the list above, but go backwards, you see that when I reduce the power, I multiply by 2 one fewer time. Equivalently, I divide by 2, or halve the number.
2^0 would be the next term in this sequence, and would be half of 2^1.
2^1=2, so 2^0 is half of that, 1.
We can go even further into negative powers, which is now explicitly dividing.
So 2^-1 = 1/2
and 2^-2 = 1/4.
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If you are worried about how ‘repeated multiplcation’, starts at 1, note that multiplcation by 1 makes no difference, so it is therefore the starting point for any multiplcation.
That is, I started earlier with 2^1 = 2.
We can multiply by 1, and this makes no difference, so
2^1 = 1×2
So by ‘repeated multiplcation’, we really mean ‘repeated multiplication *starting at 1*’, that is why 2^0=1, since we start with 1 and then do nothing to it.
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