The function f is given by f(x)=x2+1, and the function g is given by g(x)=x(x−3). Which of the following is an expression for f(g(x)) ?(A) xx3−3x2+x−3(B) x2+1x2−2(C) x2x2−6x+9+1(D) x2x2−8
Q. The function f is given by f(x)=x2+1, and the function g is given by g(x)=x(x−3). Which of the following is an expression for f(g(x)) ?(A) xx3−3x2+x−3(B) x2+1x2−2(C) x2x2−6x+9+1(D) x2x2−8
Substitute into f(x): First, we need to substitute the expression for g(x) into the function f(x).f(x)=x2+1g(x)=xx−3So, f(g(x))=f(xx−3)
Replace x in f(x): Now we will replace every instance of x in f(x) with (x−3)/x. f(g(x))=((x−3)/x)2+1
Expand binomial square: Next, we will expand the square of the binomial (xx−3)2. f(g(x))=(x2(x−3)2)+1 f(g(x))=(x2x2−6x+9)+1
Combine terms: Now we will combine the terms over a common denominator.f(g(x))=x2x2−6x+9+x2x2f(g(x))=x2x2−6x+9+x2
Simplify numerator: We simplify the numerator by combining like terms. f(g(x))=x22x2−6x+9
Check for mistakes: We notice that the expression (2x2−6x+9)/x2 is not among the answer choices, so we must have made a mistake. Let's go back and check our work.
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