Inverse functionsDoes every function have an inverse?No. A function must be 1 to 1 , or pass the horizontal line test in order to have an inverse. PASS FAIL

Notation: or 1f )(1 xf

Characteristics of an inverse function

• Algebraically– The domains and ranges are switched

• Graphically– The graphs are reflections across the line y = x

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How to find an inverse function

1. Switch x and y2. Solve for yExample: Show that andare inverses a) algebraically b ) graphically

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