Write a function cos$\_$x$\_$crossings$($begin$,$ end, skip$)$ that uses cos math function which takes begin, end and skip as input parameters, and returns the x$-$points as a Python list that crosses the x$-$axis $($i$.$e$.,$ x$-$value that just before it crosses$).$

Hint: see axis$-$crossing lecture notes for hints.

Note: you cannot use for or while loops.

Note$2$: numpy has been imported as n