If you are given the function f(x) = 10-3x and g(x) = (x-3)/2 , find the value of the composite function gf(4) ?

The composite function can be thought of as if the function f(x) is the variable for the function g(x) instead of x. So first you find the value of the function f(4),f(4) = 10 - (3x4) = 10 - 12 = -2Now that we have found the value of f(4) we have found what we need to substitute as the variable into g(x) instead of x.gf(4) = (-2-3)/2 = -5/2 = -2.5

Answered by Hajerah L. Maths tutor

2953 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Aditi, Becky and Cali collect coins. Aditi has 6 more coins than Becky. Cali has 1 less coin than Aditi. Altogether they have 71 coins. How many coins do they each have? Show all your working.


Solve the equation 3x^2 +17x -6 = 0 without using a calculator


Rectangle ABCD has sides 2x+5 and x+2 with rectangle EFGH of sides x+3 and x cut out of it. The total area of shape ABCD is 5cm^2. Show that 0 = x^2 + 6x +5 [5 Marks]


How do you solve inequalities when they involve quadratics? i.e x^2+x-6<0


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo
Cookie Preferences