Find the linear approximation of the function f(x, y, z) =
square root → x² + y² + z²
at (8, 8, 4) and use it to approximate the number
square root→ 8.01² + 7.97² + 3.98² (Round your answer to five decimal places)

f(8.01, 7.97, 3.98) ≈ ....