Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

Given the definitions of 
f(x) and 
g(x) below, find the value of 
(g@f)(-2).

{:[f(x)=x^(2)-x-11],[g(x)=-2x-4]:}
Answer:

Given the definitions of f(x) f(x) and g(x) g(x) below, find the value of (gf)(2) (g \circ f)(-2) .\newlinef(x)=x2x11g(x)=2x4 \begin{array}{l} f(x)=x^{2}-x-11 \\ g(x)=-2 x-4 \end{array} \newlineAnswer:

Full solution

Q. Given the definitions of f(x) f(x) and g(x) g(x) below, find the value of (gf)(2) (g \circ f)(-2) .\newlinef(x)=x2x11g(x)=2x4 \begin{array}{l} f(x)=x^{2}-x-11 \\ g(x)=-2 x-4 \end{array} \newlineAnswer:
  1. Understand Composition of Functions: Understand the composition of functions.\newlineThe notation g@f)(x) meansthatwefirstapply$fg@f)(x)\ means that we first apply \$f to xx, and then apply gg to the result of f(x)f(x). This is also written as g(f(x))g(f(x)).
  2. Calculate f(2)f(-2): Calculate f(2)f(-2).\newlineSubstitute 2-2 into f(x)f(x) to get f(2)f(-2).\newlinef(2)=(2)2(2)11f(-2) = (-2)^2 - (-2) - 11\newlinef(2)=4+211f(-2) = 4 + 2 - 11\newlinef(2)=611f(-2) = 6 - 11\newlinef(2)=5f(-2) = -5
  3. Calculate g(f(2))g(f(-2)): Calculate g(f(2))g(f(-2)).\newlineNow that we have f(2)f(-2), we substitute 5-5 into g(x)g(x) to get g(f(2))g(f(-2)).\newlineg(f(2))=g(5)g(f(-2)) = g(-5)\newlineg(5)=2(5)4g(-5) = -2(-5) - 4\newlineg(5)=104g(-5) = 10 - 4\newlineg(5)=6g(-5) = 6

More problems from Transformations of quadratic functions