Can you please help me find the functions?

enter image source here

2 Answers
May 14, 2018

#(g+k)(x)=g(x)+k(x) = x-3 + 2x = 3x-3#

#(hk)(x) = h(x)k(x) = (x^2-9)(2x) = 2x^3 - 18x #

#h(g(x)) = h( x-3) = (x-3)^2 -9 = x^2 - 6x #

#h(g(k(x))) = h(g(2x)) = (2x)^2 - 6(2x) = 4x^2 - 12 x#

May 14, 2018

#f(x)=x#
#g(x)=x-3#
#h(x)=x^2-9#
#k(x)=2*x#

Explanation:

1.
#(g+k)(x)=g(x)+k(x)=#

#=x-3+2*x=3*(x-1)#

2.
#(h*k)(x)=h(x)*k(x)#

#=(x^2-9)*(2*x)=2*x^3-18x#

3.
#h(g(x))=(g(x))^2-9=(x-3)^2-9=#

#=x^2-2*3*x+9-9=x^2-6*x#

4.
We can use the) result of 3. replacing #x# with #k(x)#

#h(g(k(x)))=(k(x))^2-6*k(x)=(2*x)^2-6*2*x=#

#=4*x^2-12x#