Thank you for the opportunity to help you with your question!

hello. if you notice this function, it is a parabola. Do you agree? THE DOMAIN IS ALL REAL NUMBERS. (All polynomial functions have domains defined for all real numbers.)

In the form f(x) = x*x + 7x - 4, we see the y-intercept is (0, -4) and the roots are x = -3.5 + sqrt(65)/2 and x = -3.5 - sqrt(65)/2 or (0.5311, 0) and (-7.5311, 0)

The function equation is defined for all numbers x. so in set notation the domain is { x | for x is any real number}

Domain:

Set Notation: { x | for x is any real number}

Interval Notation: (-infinity, +infinity)

Please let me know if you need any clarification. I'm always happy to answer your questions. from Alan C