When x = -4, we will use the first piece. So f(x) = x^2 when x is -4 or less than -4
Plug this into the function
f(x) = x^2
f(-4) = (-4)^2
f(-4) = 16
So when x = -4 is the input, the output is f(x) = 16
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For the second part, when x = 4, we will use the third piece. This is because f(x) = sqrt(x) when x > 1
f(x) = sqrt(x)
f(4) = sqrt(4)
f(4) = 2
When the input is x = 4, the output is f(x) = 2
