Question

If f(x) = 4 - x^2and g(x) = 6x, which expression is equivalent to (g-f)(3)?

Answer 1

23

Explanation:

(g-f)(3)=g(3)-f(3)

So we need to find g(3) and f(3). Then subtract.

g(3)=6(3)=18.

f(3)=4-(3)^2=4-9=-5.

(g-f)(3)=g(3)-f(3)=18-(-5)=18+5=23

Answer 2

(g-f)(3) = 23

Explanation:

f(x) = 4-x^2

g(x) = 6x

we need to find g-f(3)

Put the value of x = 3 in g(x) and f(x) and subtract f(x) from g(x) i.e

(g-f)(3) = g(3) - f(3)

(g-f)(3) = 6(3) - {4-(3)^2}

(g-f) (3)=18-(4-9)

(g-f)(3) = 18-(-5)

(g-f)(3) = 18+5

(g-f)(3) = 23

so, (g-f)(3) = 23