MHB Why does raising a number to the power of 0 always result in 1?

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Raising any non-zero number to the power of zero results in one due to the properties of exponents, specifically that \( a^m / a^m = a^{m-m} = a^0 \), which simplifies to one when \( a \neq 0 \). This holds true regardless of whether the base is positive or negative, as demonstrated by the example of \( (-2)^0 = 1 \) because the negative is enclosed in parentheses. Conversely, \( -1^0 \) equals negative one because the negative sign is outside the exponentiation operation, leading to \( -1 \cdot 1^0 = -1 \). The discussion also notes that \( 0^0 \) is undefined, emphasizing the importance of the base being non-zero for the exponent rule to apply. Understanding these principles clarifies why any base raised to the power of zero equals one.
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Why is base to power 0 always 1, even if it's .2^0 it =1?

Is it just counting the 1 time the .2 is existing? Is that why?And - base ^ 0 is negative whatever the number is so why is that not a negative one?

Because (-2)^2 is 4 but no because a negative times a negative is a positive.

And with parentheses -2^2 is -4, because the number is done first and then the - is kept afterwards.

So why is (-2)^0 positive 1 and -1^0 a negative?

Is it because we're doing the same thing by adding the - after when unenclosed with a ( ) ?
 
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my explanation for it:

take $\frac{x^2}{x^2}$ when x is not equal to 0. obviously it's equal to 1, right? now by the law of subtraction for exponents $x^{2-2}=1$ which is $x^0=1$ this holds for all numbers
 
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ineedhelpnow said:
my explanation for it:

take $\frac{x^2}{x^2}$ when x is not equal to 0. obviously it's equal to 1, right? now by the law of subtraction for exponents $x^{2-2}=1$ which is $x^0=1$ this holds for all numbers

More generally: Since $\displaystyle \begin{align*} \frac{a^m}{a^n} = a^{m-n} \end{align*}$, if the powers are the same then $\displaystyle \begin{align*} \frac{a^m}{a^m} = a^0 \end{align*}$. But the top and bottom are equal, and so they cancel leaving 1. So $\displaystyle \begin{align*} a^0 = 1 \end{align*}$.

Just note, $\displaystyle \begin{align*} 0^0 \end{align*}$ is undefined.
 
OMGMathPLS said:
Why is base to power 0 always 1, even if it's .2^0 it =1?

Is it just counting the 1 time the .2 is existing? Is that why?And - base ^ 0 is negative whatever the number is so why is that not a negative one?

Because (-2)^2 is 4 but no because a negative times a negative is a positive.

And with parentheses -2^2 is -4, because the number is done first and then the - is kept afterwards.

So why is (-2)^0 positive 1 and -1^0 a negative?

Is it because we're doing the same thing by adding the - after when unenclosed with a ( ) ?
In the field of discrete mathematics a precise description of why it is $\displaystyle a^{0}=1$ no matter which is a [even a=0...] il given in...

http://mathhelpboards.com/discrete-mathematics-set-theory-logic-15/difference-equation-tutorial-draft-part-i-426.html#post2479

Kind regards

$\chi$ $\sigma$
 
OMGMathPLS said:
So why is (-2)^0 positive 1 and -1^0 a negative?

Is it because we're doing the same thing by adding the - after when unenclosed with a ( ) ?

To answer your last question, yes, we are doing the same thing. $(-2)^0$ is simply $1$ because $(-2)^0=(-2)^{1-1}=\frac{(-2)}{(-2)}=1$. The negatives cancel out because they are enclosed in parenthesis (). However, $-1^0=(-1) \cdot 1^0$ has its negative outside the parenthesis so that operation is done last: $-1^0=(-1) \cdot 1^0=(-1) \cdot 1=-1$ :D
 
Another interpretation using the concept of empty function:

If we want $\left|Y^X\right|=\left|Y\right|^{\left|X\right|}$ to hold for $X=\emptyset,$ then,$$\left|Y\right|^0=\left|Y\right|^{\left|\emptyset\right|}=\left|Y^{\emptyset}\right|=1,\quad \forall \left|Y\right|=0,1,2,\ldots$$
 
I have been insisting to my statistics students that for probabilities, the rule is the number of significant figures is the number of digits past the leading zeros or leading nines. For example to give 4 significant figures for a probability: 0.000001234 and 0.99999991234 are the correct number of decimal places. That way the complementary probability can also be given to the same significant figures ( 0.999998766 and 0.00000008766 respectively). More generally if you have a value that...

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