How do i prove this is the second derivative
119053
How to prove that $\displaystyle f''(a)=\lim_{h \to 0}\frac{f(a+2h)-2f(a+h)+f(a)}{h^2}$
20904
Finding derivative of this integral function.
157918
Finding the derivative of $x^x$
39451
Proving inequation with maximum and 2nd derivative
83022
Proof of this fairly obscure differentiation trick?
84597
Derivative of $(1-x)^{-2}$
2129
Showing that the derivative operator is not bounded on $L^2 (\mathbb{R})$
124499
Where is the error in my proof that all derivatives are continuous?
1641
Proving $f' = - \frac{\partial{F}/\partial{x}}{\partial{F}/\partial{y}}$
49408
Proof of the derivative of ln(x)
30510
Second mean value theorem proof
120600
Real analysis derivate problem. How can I prove this?
88854
Simple way to understand what derivative is
71708
Proving that $\left( \frac{\partial^2}{\partial x^2} + \frac{\partial^2}{\partial y^2} \right) \lvert f(z) \rvert^2 = 4 \lvert f'(z) \rvert^2$
56712
How can I find the domain and derivative of the function?
105068
Proving that the function is differentiable and $f'(0)=0$
126445
Proving the second root of a quadratic equation