What does the transformation f(x)↦f(4x) do to the graph of f(x)?Choices:[A] stretches it vertically[B] stretches it horizontally[C]shrinks it horizontally[D]shrinks it vertically
Q. What does the transformation f(x)↦f(4x) do to the graph of f(x)?Choices:[A] stretches it vertically[B] stretches it horizontally[C]shrinks it horizontally[D]shrinks it vertically
Horizontal Scaling Explanation: The transformation f(x)↦f(4x) affects the horizontal scaling of the graph of f(x). To understand the effect, consider a point (a,b) on the graph of f(x). After the transformation, this point will be mapped to (4a,b) because f(4∗(4a))=f(a)=b. This means that every x-coordinate is scaled by a factor of 41, which makes the graph "shrink" horizontally by a factor of 4.
Elimination of Vertical Changes: Since the graph is shrinking horizontally, we can eliminate the options that suggest a vertical change (stretching or shrinking vertically). This leaves us with the choices that involve horizontal changes.
Selection of Horizontal Shrink: Between the two remaining options, "stretches it horizontally" and "shrinks it horizontally," we have already established that the transformation causes a horizontal shrink, not a stretch. Therefore, the correct choice is "shrinks it horizontally."