Question

4. Sejam as funções definidas f(x)= x-1 e g(x)= 2x-7
a) Obter as leis que definem fOg e gOf
b) Calcular (fOg) (4) e (gOf)(4)

Answer 1

$f(x)=x-1\\g(x)=2x-7\\\\\\a)\\ f(g(x))= (2x-7)-1= 2x-8\\g(f(x))= 2(x-1)-7= 2x-2-7=2x-9\\\\\\b)\\f(g(4))= 2(4)-8 = 8-8 = 0\\g(f(4))= 2(4)-9= 8-9= -1$