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Evaluate and invert a functionTechnique

Technique

Evaluate and invert a function

Input given, substitute; output given, solve

3 min 3 steps

Every function question hands you one end: the input or the output. I once grabbed a marker by the wrong end in front of the whole class.

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The first step is free. A free account opens the rest.

Calls on

Function notation and vertical shiftsFactSwap in the input; add outside to shift up

Used by

Match or verify a representationTacticTest the point where the choices disagree
Build a linear function from two factsTacticSlope from the change, intercept from one point
Evaluate, invert, and transformTacticFind the missing end, then let the slope carry changes
Build and analyze an exponential modelTacticPin the start and the factor; every step follows
Evaluate, compose, and transformTacticSubstitute the whole input, parentheses and all
Polynomial zeros, factors, and graphsTacticTurn zeros into factors and factors into graphs