Find (f/g)(4) and (f+g)(4)?

If f(x)=x^2+2x-3 and g(x)=x^2-9, Find (f/g)(4) and (f+g)(4)

2 Answers
Jun 21, 2018

#(f/g)(4)=(f(4))/(g(4))=(21)/7=3#
#(f+g)(4)=f(4)+g(4)=21+7=28#

Explanation:

The notation #(f/g)(x)# is just a way to say #(f(x))/(g(x))# and
#(f+g)(x)# is another way to say #f(x)+g(x)#
#(fg)(x)# is another way to say #f(x)*g(x)#

Jun 21, 2018

#(f/g)(4)=3#, #(f+g)(4)=28#

Explanation:

#f(x)=x^2+2x-3# , #g(x)=x^2-9#
#f(4)=4^2+2*4-3=16+8-3=21#
#g(4)=4^2-9=16-9=7#

#(f/g)(4)=f(4)/g(4)#

#(f/g)(4)=21/7=3#

#(f+g)(4)=f(4)+g(4)#

#(f+g)(4)=21+7=28#