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Functions
Functions map an input to an output. For example, the function f(x) = 2x takes an input, x, and multiplies it by two. An input of x = 2 gives you an output of 4. Learn all about functions.
Excel in math and science
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Given two functions:
\(f(x)=x+3\)
\(g(x)=\dfrac{x}{2}\)
Find the value of \(g(f(5))\).
Excel in math and science
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by Brilliant Staff
For the two functions \[f(x)=x^2+5x, \, g(x)=x+22,\] what is the value of \((g \circ f)(9)?\)
Details and assumptions
\( (g \circ f)(x) \) is the composition of \(g\) and \(f\), defined by \((g \circ f)(x)= g(f(x))\).
Excel in math and science
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Let \(f\) be a function such that \((f \circ f)(x) = x^2\)
What is the value of \(f(f(f(f(f(f(2))))))?\)
Excel in math and science
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Consider the two functions \[f(x)=6x-5, g(x)=\begin{cases} -x+4 & \text{ if } x \geq 1, \\ 17 & \text{ if } x<1. \end{cases}\] What is the value of \((f \circ g)(2)+(g \circ f)(0)\)?
Details and assumptions
\( (g \circ f)(x) \) is the composition of \(g\) and \(f\), defined by \((g \circ f)(x)= g(f(x))\).
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\( f: \mathbb{R} \rightarrow \mathbb{R}\) is a function satisfying \( f( 2x+1) = 4x^2 + 4x\). What is the value of \(f(16)\)?
Excel in math and science
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by Brilliant Staff