is..... rational fraction

Explanation

We cannot definitively say whether this is a proper or improper rational fraction without further analysis.A proper rational fraction has a numerator whose degree (highest power of the variable) is less than the degree of the denominator.An improper rational fraction has a numerator whose degree is equal to or greater than the degree of the denominator.In this case, the numerator's degree (1) is less than the denominator's degree (2). However, it's important to note that the denominator, x^2 + 4, can be factored as (x + 2)(x - 2). This means the expression is equal to zero when x = -2 or x = 2. Dividing by zero is undefined, so for the fraction to be a valid mathematical expression, the values of x that make the denominator zero (x = -2 and x = 2) must be excluded.Since the fraction's validity depends on the value of x, it can't be definitively classified as proper or improper without further context.