266. Inside the square $A B C D$, an isosceles triangle $A B L$ is constructed with base $A B$ and base angles of $15^{\circ}$. Under what angle is the side $C D$ seen from the vertex $L$?
$\triangleright$ Of course, this problem essentially coincides with the previous one: construct an equilateral triangle $C D M$ inside the square, then $A M$ and $B M$ will exactly form a $15^{\circ}$ angle with the sides, so $M$ will coincide with $L . \triangleleft$

If you don't know the previous problem, this one

![](https://cdn.mathpix.com/cropped/2024_05_21_90703b5d5e76e3b5cd3dg-079.jpg?height=386&width=323&top_left_y=732&top_left_x=341)
will turn out to be quite difficult - it's not clear how to guess that triangle $C D L$ is equilateral without knowing it in advance