Question

Sendp f(x)= x-7 resolva, f(f(x))= -1/3

Answer 1

f(x) = x - 7

f(f(x)) = -1/3

daí: f(x-7) = -1/3
         
       (x-7) - 7 = -1/3
        x-7 -7 = -1/3 
        x = -1/3 + 14
        x = (-1 + 42)/3
        x = 41/3

Answer 2

Boa noite Clara 

f(x) = x - 7

f(f(x)) = (x - 7) - 7 = x - 14

x - 14 = -1/3
x = 14 - 1/3
x = 42/3 - 1/3
x = 41/3

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