Question 310649
Hello, 
It's undefined when both s and x are zero or when the two numbers come out to zero for example if s is 3 and x is -3.
(Hint: if zero is in the denominator it's undefined, however when zero is in the numerator the answer is zero. Use your calculator and punch in 0 divided by any number. What do you get? Now divide a number by zero. What do you get? See the "E" it means error as it is undefined)
Make sense? 
RJ
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