The problem asks to find the function that results from transforming $f(x) = \log_{10}x$ by a vertical stretch by a factor of 4, horizontal stretch by a factor of 3, reflection in the y-axis, horizontal translation 5 units to the right, and vertical translation 2 units up.

AlgebraFunction TransformationsLogarithmic FunctionsTransformations of Graphs
2025/4/10

1. Problem Description

The problem asks to find the function that results from transforming f(x)=log10xf(x) = \log_{10}x by a vertical stretch by a factor of 4, horizontal stretch by a factor of 3, reflection in the y-axis, horizontal translation 5 units to the right, and vertical translation 2 units up.

2. Solution Steps

The original function is f(x)=log10xf(x) = \log_{10}x.
Vertical stretch by a factor of 4: 4log10x4\log_{10}x.
Horizontal stretch by a factor of 3: 4log10(x/3)4\log_{10}(x/3). Note that a horizontal stretch by a factor of 3 means replacing xx by x/3x/3. This gives f(x)=4log10(x/3)f(x)=4\log_{10}(x/3).
Reflection in the y-axis: 4log10(x/3)4\log_{10}(-x/3).
Horizontal translation 5 units to the right: 4log10((x5)/3)4\log_{10}(-(x-5)/3).
Vertical translation 2 units up: 4log10((x5)/3)+24\log_{10}(-(x-5)/3) + 2.
Simplifying the argument inside the logarithm: 4log10((x5)3)+2=4log10(x+53)+24\log_{10}(\frac{-(x-5)}{3}) + 2 = 4\log_{10}(\frac{-x+5}{3}) + 2.
An alternative approach is to first take f(x)=log10(x)f(x)=\log_{10}(x), then f(x/(13))=log10(x13)=log10(3x)f(x/(\frac{1}{3}))=\log_{10}(\frac{x}{\frac{1}{3}})=\log_{10}(3x).
Reflection in the y-axis means we replace x by -x to get log10(3x)\log_{10}(-3x).
A horizontal translation 5 units to the right means we replace x by (x-5), i.e., f(x5)f(x-5).
So we have f(x)=log10(3(x5))f(x)=\log_{10}(-3(x-5)).
Vertical stretch by a factor of 4 gives 4log10(3(x5))4\log_{10}(-3(x-5)).
Vertical translation 2 units up gives 4log10(3(x5))+24\log_{10}(-3(x-5))+2.

3. Final Answer

f(x)=4log10[3(x5)]+2f(x) = 4\log_{10}[-3(x-5)] + 2