What equation undoes f(x) = 2x + 3?
An inverse function undoes whatever the original did. Here f multiplies by 2 and adds 3, so the inverse must unwind both in reverse.
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1 lesson for “Inverse functions”
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What is f(-2) when f(x) = x^2 - 4x?
f(x) is a rule with a name, not multiplication. f(-2) means: feed -2 into the rule and see what comes out.
Try this lessonWhich x values are allowed in f(x) = 1/(x - 2)?
A function's domain is the list of numbers you may feed it. A zero denominator is one number that is never allowed.
Try this lessonDoes doubling pressure double the volume?
Double the pressure and the volume halves; double the kelvin temperature and it doubles. Match each law to its direction.
Try this lessonWhat is the opposite of adding 7?
Owen solved x + 7 = 12 by computing 12 + 7 = 19. He added again instead of undoing the addition.
Try this lessonWhat power solves 2^x = 32?
A logarithm asks one question: what exponent do I need? log3(81) says: 3 to what power gives 81?
Try this lessonWhat slope makes a line perpendicular to y = 2x + 7?
Two lines can look very different and still be perfect partners. The slope alone tells you whether they are parallel or perpendicular.
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