Why is the $\frac{1}{2}$ significant in $\frac{1}{2}\rho v^2 C_d A$?
71186
Why is the drag force proportional to $v^2$ and defined with a factor of $1/2$?
147528
Where's the error in this $2=1$ fake proof?
28254
Why $\sum_{k=1}^{\infty} \frac{k}{2^k} = 2$?
44239
Why the extra term $\frac{1}{2}(\partial_{\rho}A^{\rho})^2$ in the photon Lagrangian?
43184
Using the Residue Theorem to Prove that $\int^{2\pi}_{0} \frac{1}{(a+\cos\theta)^{2}} d \theta=\frac{2\pi a}{(a^{2}-1)^{3/{2}}}.$
95145
Does $\exp(2ir\pi)$ equal $1$? What's wrong?
885
Why is the 2nd derivative written as $\frac{\mathrm d^2y}{\mathrm dx^2}$?
128764
How does $y[x] = a x^r$ when $y'[x] = \frac{(r y[x])}{x}$ and $y[1] = a$
123392
How does $cos(x) = \frac{\vec{v} \cdot \vec{w}}{|\vec{v}| \cdot |\vec{w}|}$ make sense?
27969
Why does $\frac{1}{x} < 4$ have two answers?
72906
Is $\frac{\partial}{\partial x_1}=\frac{\partial}{\partial y_1}$ if $x_1=y_1$?
153794
What is the meaning of $1/(D+a)$, where $D$ is the derivative operator?
129236
Continued fraction for $\frac{1}{e-2}$
29578
Why is $\binom{2n}{n} \asymp \Theta \big(\frac{2^{2n}}{\sqrt{n}}\big)$?
144439
For a $C^1$ function, the difference $|{g'(c)} - {{g(d)-g(c)} \over {d-c}} |$ is small when $|d-c|$ is small
81057
Evaluation of $\int_{\frac{1}{e}}^{\tan x}\frac{t}{1+t^2}dt+\int_{\frac{1}{e}}^{\cot x}\frac{1}{t(1+t^2)}dt$
117922
Is $\frac{a+b}{c+d}0$?