RATIONAL FUNCTIONS Solving Rational Inequalities (Page 3 of 3)

Since the x-intercept has a y-value equal to 0, it is part of the solution set. The x-values (on the first branch) to the left of the vertical asymptote x = -1 yield negative y-values. The values of x (on the right branch) between the vertical asymptote and the intercept x = 4 produce positive y-values. The x-values to the right of the intercept again yield negative y-values.

The inequality (x+6)/(x+1)-2 >= 0 means that the graph of Y1 must lie on or above the x-axis. By observing the graph, we see this is true if x is between -1 and 4, including x = 4 but not including x = -1 (because the function is undefined). So, the solution set is {x: -1 < x <= 4}, or in interval notation, (-1, 4].

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