Let f(x)=xf(x)=\sqrt{x} and g(x)=xg(x)=x be two functions defined over the set of nonnegative real numbers. Find (f+g)(x),(f−g)(x),(fg)(x)(f+g)(x),(f-g)(x),(f g)(x) and (fg)(x)\left(\frac{f}{g}\right)(x).

Answer: (f+g)(x)=x+x(f−g)(x)=x−x(fg)(x)=x3/2(fg)(x)=1x(f+g)(x) = \sqrt{x} + x \\ (f-g)(x) = \sqrt{x} - x \\ (fg)(x) = x^{3/2} \\ \left(\frac{f}{g}\right)(x) = \frac{1}{\sqrt{x}}

Step-by-step solution

Step 1: Define the functions

We are given two functions, f(x)=xf(x) = \sqrt{x} and g(x)=xg(x) = x. Both functions are defined for nonnegative real numbers, meaning x≥0x \ge 0.

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. So, we add f(x)f(x) and g(x)g(x) to get x+x\sqrt{x} + x.

Step 3: Calculate the difference of functions

The difference of two functions, (f−g)(x)(f-g)(x), is found by subtracting g(x)g(x) from f(x)f(x). This results in x−x\sqrt{x} - x.

Step 4: Calculate the product of functions

The product of two functions, (fg)(x)(fg)(x), is found by multiplying f(x)f(x) and g(x)g(x). We can write x\sqrt{x} as x1/2x^{1/2}. When multiplying powers with the same base, we add the exponents, so x1/2⋅x1=x3/2x^{1/2} \cdot x^1 = x^{3/2}.

Step 5: Calculate the quotient of functions

The quotient of two functions, (fg)(x)\left(\frac{f}{g}\right)(x), is found by dividing f(x)f(x) by g(x)g(x). We subtract the exponents when dividing powers with the same base, so x1/2/x1=x−1/2x^{1/2} / x^1 = x^{-1/2}. This can also be written as 1x\frac{1}{\sqrt{x}}. Note that for the quotient, g(x)g(x) cannot be zero, so x≠0x \ne 0.

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