Tan(pi/2)=complex infinity why?

  • Thread starter Thread starter GreenPrint
  • Start date Start date
  • Tags Tags
    Infinity
GreenPrint
Messages
1,186
Reaction score
0

Homework Statement


Hi,

I have just now come to the realization that tan(pi/2) is not infinity but complex infinity. I was wondering why and can't seem to find the answer. I was told all through high school that tan(pi/2)=infinity or undefined but not complex infinity.

Homework Equations


The Attempt at a Solution

 
Physics news on Phys.org
GreenPrint said:

Homework Statement


Hi,

I have just now come to the realization that tan(pi/2) is not infinity but complex infinity. I was wondering why and can't seem to find the answer. I was told all through high school that tan(pi/2)=infinity or undefined but not complex infinity.

Homework Equations





The Attempt at a Solution


It depends what number system you're working in.

Real numbers: undefined

Extended real numbers: infinity

Riemann sphere: infinity
 
Interesting, thanks!
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...

Similar threads

Back
Top