@CliffSedge

how many of the following relations are functions of f on R(real numbers)

y = root(x)
y = x^3
y = |x|
y = x^(2/3)
|y| = |x|

i got 4, all of them are except y = root(x)

???

Question

@CliffSedge 
 
how many of the following relations are functions of f on R(real numbers)


y = root(x)
y = x^3
y = |x|
y = x^(2/3)
|y| = |x|

i got 4, all of them are except y = root(x)


???

anonymous · Answer

Do you mean, which have real number function values for any value of x?

anonymous · Answer

or alternatively, which have an unrestricted domain of x?
If so, then yes, only sqrt(x) has its domain restricted to non-negative numbers to keep the range real, though |y|=|x| looks a little funny..

anonymous · Answer

yup the real number function values for any value of x!