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Difference between revisions of "Square roots are always nonnegative"

(Square roots are always nonnegative)
 
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== Square roots are always nonnegative ==
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Many people get confused, thinking that <math>x^2 = 16</math> and <math>x= \sqrt{16}</math> are the same. Though both of these are similar, one of them only has one answer. If we take <math>x^2 = 16</math>, we can see that it has <math>2</math> answers; <math>4</math> and <math>-4</math>. On the other hand, <math>x = \sqrt{16}</math> only has one.
 
 
Many people around the world get confused, thinking that <math>x^2 = 16</math> and <math>x= \sqrt{16}</math> are the same. Though both of these are similar, one of them only has one answer. If we take <math>x^2 = 16</math>, we can see that it has <math>2</math> answers; <math>4</math> and <math>-4</math>. On the other hand, <math>x = \sqrt{16}</math> only has one.
 
  
  
 
'''Square Root''' is a function, and a function cannot have two different answers for one input. Technically <math>-4</math> and <math>4</math> are "square roots" of <math>16</math>, but the square root function only represents one of them--the ''nonnegative'' answer.
 
'''Square Root''' is a function, and a function cannot have two different answers for one input. Technically <math>-4</math> and <math>4</math> are "square roots" of <math>16</math>, but the square root function only represents one of them--the ''nonnegative'' answer.

Latest revision as of 13:51, 16 May 2025

Many people get confused, thinking that $x^2 = 16$ and $x= \sqrt{16}$ are the same. Though both of these are similar, one of them only has one answer. If we take $x^2 = 16$, we can see that it has $2$ answers; $4$ and $-4$. On the other hand, $x = \sqrt{16}$ only has one.


Square Root is a function, and a function cannot have two different answers for one input. Technically $-4$ and $4$ are "square roots" of $16$, but the square root function only represents one of them--the nonnegative answer.