if f(x)=3x^2 and g(x)=x+3 ,find (f-g)(x)

Answer 1

By definition, (f-g)(x) = f(x) - g(x).

If f(x) = 3x² and g(x) = x + 3, then (f-g)(x) = f(x) - g(x) = (3x²) - (x + 3) = 3x² - x - 3

Answer 2

Simply take the difference so (f-g)(x) = 3x² − x − 3