Can X=2 and X=-2 at the same time?

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ahh but root uses a double o and all the letters are on the same line ... its just more efficient haha
 
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It may be more efficient but it's also ambiguous. We could use "root" to represent any nth root whereas "sqrt" specifically denotes the squareroot.
 


so (sqrt 1 - sqrt 1) is different to
x=sqrt 1
x-x
 


chalky00 said:
so (sqrt 1 - sqrt 1) is different to
x=sqrt 1
x-x
(sqrt 1 - sqrt 1) has 4 possible solutions.
 


chalky00 said:
so (sqrt 1 - sqrt 1) is different to
x=sqrt 1
x-x

No! Hopefully without confusing you too much, if we let [itex]x = \sqrt{1}[/itex] then [itex]x=1[/itex] because the [itex]\sqrt[/itex] operation retrieves the principal (positive) square root. However, if [itex]x[/itex] is a number such that [itex]x^2 = 1[/itex] then [itex]x=1[/itex] or [itex]x=-1[/itex]. Now, using this second definition of [itex]x[/itex], once we choose a value for [itex]x[/itex] we need to stick with it. We can't have [itex]x = 1[/itex] and [itex]x = -1[/itex] at the same time because this would violate the law of non-contradiction and you're already assuming that [itex]1 = -1[/itex].
 


Stop feeding the troll (OP)!