Thread: Lost in this one, dimensions

1. Lost in this one, dimensions

Find, correct to five decimal places, the dimensions of the rectangle of largest area that has its base on the x-axis and its other two vertices above the x-axis and lying on the curve $y = cos x$ .

I have no idea where to begin... I don't even be clear what it wants for the result

A = bh = x.cos(x)

and then evaluate A'=0 to find the points but I got stuck in the process, I missed something or maybe I'm evaluating the wrong area.

3. Originally Posted by dax918
But this problem, as stated, has no solution. Taking the left side at $x_0$, we can take the right side at $x+ 2n\pi$ having arbitrarily large area. There is NO "largest area".