Let fx Squareroot x gx x 12 and hx 4x Compute the follow

Let f[x) = Squareroot x, g(x) = x + 12 and h(x) = 4/x. Compute the following function value. (f + g)(9) Let f(x) = Squareroot x, g(x) = x + 9 and h(x) = 5/x. Compute the following function value. (g - h) (7) Let f(x) = Squareroot x, g(x) = l0 and h (x) = 2/x. Compute following function value. (fh) (9) Let f(x) = Squareroot x, g (x) = x + 10 and h(x) = 2/x. Compute the following function value (h/g)(4)

Solution

1) f(x) = sqrtx ; g(x) = x+12

h(x) = 4/x

(f +g)(x) = f(x) +g(x) = sqrt(x) +x +12

(f +g)(9) = sqrt(9) + 9 +12 = 3 +9 +12 = 24

2)

f(x) = sqrtx ; g(x) = x+9

h(x) = 5/x

(g - h)(x) = x+9 - sqrtx

( g - h)(7) = 7 +9 - sqrt(7) = 16 -sqrt7

3) f(x) = sqrtx ; g(x) = x+10 ; h(x) = 2/x

(fh)(x) = sqrt(x)*2/x

(fh)(9) = sqrt(9) *2/9 = 2/3

4) f(x) = sqrtx , g(x) = x +10 and h(x)= 2/x

(h/g)(x) = h(x)/g(x) = (2/x)/(x+10)

= 2/(x^2 +10x)

(h/g)(4) = 2/(4^2 +40)

= 2/(56)

= 1/28