fxx28x7 gxx7 fgx fgx fgx fgx Given the following functions f

f(x)=x2+8x+7

g(x)=x+7

(f+g)(x)=

(fg)(x)=

(fg)(x)=

(fg)(x)=

Given the following functions, find (fg)(5):

f(x)=2x3

g(x)=x+1

Solution

f(x)=x^2+8x+7

g(x)=x+7

(f+g)(x)= f(x) + g(x)

             = x^2 +8x+7 +x+7

            =x^2 +9x +14

(f -g) (x) = f(x) - g(x)

               =(x^2 +8x +7) - (x+7)

               = x^2 +7x

(f. g) (x) = f(x) .g(x)

              = (x^2 +8x+7).(x+7)

              = (x^3 +7x^2 +8x^2 +56x+7x+49 )

              =(x^3 +15x^2 +63x +49)

(fg) (x) = (f.g) (x)

so same answer as above one

given the following functions, find (fg)(5):

f(x)=2x3

g(x)=x+1

(fg) (-5) = f(-5).g(-5)

f(-5) = -2(-5) -3 = 10 - 3 =7

g(-5) = -5 +1 =-4

(fg) (-5) = f(-5).g(-5)

              = 7 x -4

              = -28