The Machine That Feeds a Machine

You'll learnto run a composition f(g(x)) in the correct order.

Composition chains two functions: the output of one becomes the input of the other. Every point this topic costs comes from one confusion — reading f(g(x)) left to right and running f first. Watch a value travel through the chain the right way, watch the wrong order produce a different number, and watch the domain gate stop an input cold.

8 STEPS · 6 QUICK CHECKS · f(g(x)) — INSIDE ACTS FIRST · v3

f(g(x))

Before you start

What you're looking at

Two machines, f and g, chained so one's output feeds the other, with a value about to travel through.

The question

In f(g(2)), which function acts first?

Watch for

The inner function touching the input goes first — reading left to right runs it backward.

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