Where cos(x) intersects sin(x)

[alpha01]

we know that cos(x) intersects sin(x) in the interval 0< x< pi/2... but how can i find (x,y) points of this intersection? (without plotting and estimating based of the resultant graph)

 

[HallsofIvy]

If cos(x)= sin(x) then sin(x)/cos(x)= tan(x)= 1. Solve that equation.

 

[epenguin]

In a right angled triangle with hypotenuse of length 1 and one angle x, the side next that angle is cos x, the side opposite ... need I say more?