Let f(x)=x2f(x)=x^{2} and g(x)=2x+1g(x)=2 x+1 be two real functions. Find (f+g)(x),(f−g)(x),(fg)(x),(fg)(x).(f+g)(x),(f-g)(x),(f g)(x),\left(\frac{f}{g}\right)(x) .

Answer: (f+g)(x)=x2+2x+1(f+g)(x) = x^2 + 2x + 1, (f−g)(x)=x2−2x−1(f-g)(x) = x^2 - 2x - 1, (fg)(x)=2x3+x2(fg)(x) = 2x^3 + x^2, (fg)(x)=x22x+1\left(\frac{f}{g}\right)(x) = \frac{x^2}{2x+1} for x≠−12x \neq -\frac{1}{2}.

Step-by-step solution

Step 1: Define the functions

We are given two real functions, f(x)=x2f(x) = x^2 and g(x)=2x+1g(x) = 2x+1. We need to find their sum, difference, product, and quotient.

Step 2: Calculate the sum of functions

The sum of two functions, (f+g)(x)(f+g)(x), is found by adding their individual expressions. We substitute f(x)f(x) and g(x)g(x) and combine like terms.

Step 3: Calculate the difference of functions

The difference of two functions, (f−g)(x)(f-g)(x), is found by subtracting the second function from the first. Remember to distribute the negative sign to all terms of g(x)g(x).

Step 4: Calculate the product of functions

The product of two functions, (fg)(x)(fg)(x), is found by multiplying their individual expressions. We use the distributive property to multiply x2x^2 by each term in 2x+12x+1.

Step 5: Calculate the quotient of functions

The quotient of two functions, (fg)(x)\left(\frac{f}{g}\right)(x), is found by dividing the first function by the second. It is important to note that the denominator cannot be zero, so we must exclude values of xx for which 2x+1=02x+1=0. This means x≠−12x \neq -\frac{1}{2}.

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