Function Composition Formula:
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Definition: Function composition combines two functions where the output of one function (g) becomes the input of another (f).
Notation: \((f \circ g)(x) = f(g(x))\) means "f of g of x".
The composition process:
Example 1: If f(x) = x² and g(x) = x + 1
Then (f ∘ g)(x) = f(g(x)) = f(x + 1) = (x + 1)²
Example 2: If f(x) = √x and g(x) = 2x - 3
Then (f ∘ g)(x) = f(2x - 3) = √(2x - 3)
Instructions:
Q1: Is function composition the same as multiplication?
A: No, composition is different from multiplication. f(g(x)) is not the same as f(x)*g(x).
Q2: Can I compose more than two functions?
A: Yes, like (f ∘ g ∘ h)(x) = f(g(h(x))). The calculation proceeds from right to left.
Q3: Is function composition commutative?
A: No, f(g(x)) is generally not equal to g(f(x)). Order matters in composition.
Q4: What's the domain of a composite function?
A: The domain consists of all x in g's domain where g(x) is in f's domain.
Q5: How is this used in real applications?
A: Composition models complex relationships where one process's output feeds into another.