- #1
camino
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Homework Statement
Use linear approximation to approximate sqrt((3.2)^2 + 2(2.1) + (4.3)^2)
with a rational number (a ratio of integers).
Homework Equations
f(x,y) = sqrt(x^2 + 2y + z^2)
f(x,y) = (x^2 + 2y + z^2)^1/2
The Attempt at a Solution
x = 3 ∆x = 2/10
y = 2 ∆y = 1/10
z = 4 ∆z = 3/10
≈ sqrt(3^2 + 2(2) + 4^2) + [3/sqrt(3^2 + 2(2) + 4^2)] (2/10) + [2/sqrt(3^2 + 2(2) + 4^2)] (1/10) + [4/sqrt(3^2 + 2(2) + 4^2)] (3/10)
≈ [sqrt(29)] + [6/sqrt(29)(10)] + [2/sqrt(29)(10)] + [12/sqrt(29)(10)]
I'm not sure where to go from here to simplify it down to a single ratio. Am I on the right track?