0
$\begingroup$

Compute the number of ordered pairs $(x,y)$ that satisfy the system $$\begin{align*} \sin(x+y)&=\cos(x+y)\\ x^2+y^2&=\left(\dfrac{1995\pi}{4}\right)^2 \end{align*}$$

I got 5622, but I'm not sure if that's correct. Can someone provide a hint?

  • 1
    It would perhaps help if you gave some indication of your workings - which solutions have you found? Then it would be possible for us to identify whether you have missed something, or alternatively if you have double-counted somewhere.2012-04-07

2 Answers 2