Question

F(x)=−7x^2 −x and g(x)=9x^2 −4x , find (f−g)(x) and (f−g)(1)

Answer 1

f(x) = -7x² - x

g(x) = 9x² - 4x

To find ( f - g)(x) subtract g(x) from f(x)

That's

( f - g)(x) = - 7x² - x - ( 9x² - 4x)

= -7x² - x - 9x² + 4x

Group like terms

( f - g)(x) = - 7x² - 9x² - x + 4x

( f - g)(x) = - 16x² + 3x

To find (f - g)(1) substitute 1 into ( f - g)(x)

That's

(f - g)(1) = - 16(1) + 3(1)

= -16 + 3

= - 13

Hope this helps you