state the domain and range f(x)=x 1/3
is this written as \[f(x) = 1/3x?\]
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oh....its \[f(x) = x ^{1/3}\] ?
yes
okay....so...are there ANY values of x...that can make this function not = a real number?
keep in mind...raising to the 1/3 power...is the same as taking the cubed root of a number.....so think....are there any numbers you cannot take a cubed root (or a square root) of?
yes 3
....well you can still evaulate 3 correct? it will be a decimal...but still a number right? let me ask you...what is the square root of -1?
you can't do it
exactly....so that wouldn't be in the domain....what about the square root of 0? can you do it?
nope 0
well yes you can...it would be 0 like you said....as long as you can GET a number...then it exists in the domain...so ...what we have here is...the domain cannot be negative...but can be 0....and can go as high as it wants right? so domain [0,infinity) range...is the y values.....how big and how small of numbers do you get for plugging in the smallest x you can...and the biggest x you can?
you can do 1 and 3 for the rang right
so say you plug in 0 for x...what does y =? say you plug in a REALLLLLY big number for x? an even bigger number? is there any limit? no so that is [0,infinity as well)
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