The graph of has an axis of symmetry. What is the reflection of the point over this axis?
Pick one
Solution
Let . Because approaches infinity as increases without bound, the only possible axis of symmetry is a vertical line. If the axis of symmetry has equation , then for every real , which is equivalent to . Multiplying through by and simplifying gives . Because this equation holds for all , it follows that and . Thus . The reflection of with respect to the vertical line is .
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