Q. Given the definitions of f(x) and g(x) below, find the value of (g∘f)(−7).f(x)=2x+15g(x)=2x2+5x+4Answer:
Understand Notation: First, we need to understand the notation (g@f)(x). This notation means that we first apply the function f to x, and then apply the function g to the result of f(x). This is also known as the composition of functions, denoted by (g∘f)(x).
Find f(−7): Now, let's find f(−7) using the definition of f(x)=2x+15.f(−7)=2(−7)+15=−14+15=1.
Find g(f(−7)): Next, we will use the result of f(−7) to find g(f(−7)) by substituting 1 into g(x), where g(x)=2x2+5x+4.g(1)=2(1)2+5(1)+4=2+5+4=11.
Conclude Result: Since we have found g(1), and we know that f(−7)=1, we can conclude that (g@f)(−7) is equal to g(f(−7)) which is g(1). Therefore, (g@f)(−7)=11.
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