Question 1117791
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Concretely for  f(x) = {{{abs(x)/x}}},  this function takes only TWO values:


    if  x > 0,  then |x| = x, and therefore  f(x) = {{{x/x}}} = 1.


    if  x = 0,  then the function f(x) is NOT DEFINED.


    if  x < 0,  then |x| = -x,  hence  f(x) = {{{(-x)/x}}} = -1.



So, the range of this function is the set of the two values  {-1,1},  while its domain is the set of all real numbers except of {0}.
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To be successful at the exam, &nbsp;you need 


&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1) &nbsp;to know the basics well,  &nbsp;and  


&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2) &nbsp;to have some experience in solving typical problems.