# Calculus

If f(x) = sqrt x + 3/sqrt x, then f’(4) =

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1. since √x = x^(1/2)
f(x) = x^(1/2) + 3x^(-1/2)
f'(x) = 1/2 x^(-1/2) - 3/2 x^(-3/2)
and plugging in x=4, that is
f'(4) = (1/2)(1/2) - (3/2)(1/8) = 1/16

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oobleck
2. 4√a-3=10

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