Question 1021714
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{{{y=x/(x^2+4)}}}
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Since x^2+4 never equals zero (when x is real), there are no 
vertical asymptotes.
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Note there are no discontinuities in the domain of the graph, 
thus no point x could "approach but never reach"
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{{{ graph( 800, 800, -10, 10, -10, 10, x/(x^2+4)) }}}