Find the domain of the function f(x)=x2+3x+5x2−5x+4f(x)=\frac{x^{2}+3 x+5}{x^{2}-5 x+4}

Answer: The domain of the function is all real numbers except 11 and 44, which can be written as R∖{1,4}\mathbb{R} \setminus \{1, 4\}.

Step-by-step solution

Step 1: Identify the restriction for rational functions

For a rational function, the denominator cannot be equal to zero. If the denominator were zero, the function would be undefined at that point. Therefore, we must find the values of xx that make the denominator zero and exclude them from the domain.

Step 2: Factor the quadratic denominator

To find the values of xx that make the denominator zero, we factor the quadratic expression x2−5x+4x^2 - 5x + 4. We look for two numbers that multiply to 4 and add up to -5. These numbers are -1 and -4, so the factored form is (x−1)(x−4)(x-1)(x-4).

Step 3: Solve for x

Setting each factor equal to zero gives us the values of xx that make the denominator zero. Thus, x=1x=1 and x=4x=4 are the values for which the function is undefined.

Step 4: State the domain

The domain of the function includes all real numbers except for the values that make the denominator zero. Therefore, the domain is all real numbers except 1 and 4.

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