find f(-4),f(-3.1),f(1.2)and f (2.8)for f(x)=x

Answer:The answer is f(-4) = -4 ,f(-3.1) = -3.1 ,  f(1.2) = 1.2 , f(2.8) = 2.8Step-by-step explanation:    We have to find out f(-4) , f(-3.1) , f(1.2) , f(2.8)     For the condition f(x) = x     This means that whatever we give input to the function the value to the      function is equal to the value input this means that     f (input) = output     Here output = input     f ( input ) = input     ∵ f(-4) = -4        f(-3.1) = -3.1        f(1.2) = 1.2        f(2.8) = 2.8