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Lebl-Basic-Analysis-I
· Problem 4.1.1
The Derivative
Mathematics · derivative-product-rule
Problem
Prove the product rule. Hint: Prove and use
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f(x)g(x) - f(c)g(c) = f(x)\bigl(g(x) - g(c)\bigr) + \bigl(f(x) - f(c)\bigr)g(c)
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