Teach me something new. Anything

Teach me something new. Anything.

[math] e^{i\pi} + 1 = 0 [/math]

[eqn]A = PDP^{-1}[/eqn]

(tan x)' = sec^2 x

those who can't, just instruct others and act like victims

-Joshua 6:14

If [math] r_2^2-\left(\frac{d^2+r_1^2-r_2^2}{2d}\right)^2 = \frac{\left(d^4+2r_1^2r_2^2-r_1^4-r_2^4\right)^2}{16d^4\left(r_2^2-\left(\frac{r_1^2-r_2^2-d^2}{2d}\right)^2 \right)} [/math]
,where d is the distance between two cicles, r1 is the radius of the first circle and r2 is the radius of the second circle, then the radius of the first circle is a tangent to the second. I hope I didn't fuck that up

the average BBC is 8 inches in length.

x=1

associativity of addition does not hold in general for infinite series

P = NP