y = x^(1/4)
y' = 1/4 x^(-3/4)
at (7,2401) y' = -1/1372
so, since ∆y ≈ dy/dx * ∆x,
∆y ≈ (-1/1372)(-11) = 0.00802
making
∜2390 ≈ 7.008
real value: 6.992
makes sense, since the graph is concave down, so the tangent line will overestimate the true value.
Use tangent line approximation to estimate fourth root of 2390 (to seven decimal places) recognizing that 7^4=2401. Show all your work.
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