Sect 1.6--Inverse Functions Day 2
How to find an inverse function once you know it exists...
Given: f(x) = 3x ­7
Step 1: y = 3x - 7
1: Replace f(x) with y
Step 2: x = 3y - 7
2. Switch x and y
Step 3: x + 7 = 3y
3. Solve for y
REMINDER:
It has to be a function and an inverse must exist prior to doing these steps. x+7=y
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Step 4: x + 7 = f-1(x)
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4. Replace y with f-1(x)
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Example: Find the inverse of...
1. f(x) = x + 3
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Example: Find the inverse of...
2. y = x3 - 1
3. y = x2 + 2x - 3
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Homework...
Section 1.6
See the assignment sheet for specific problems
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