Solve for $$y$$ if $${{{d^2}y} \over {d{t^2}}} + 2{{dy} \over {dt}} + y = 0$$ with $$y(0)=1$$ and $${y^1}\left( 0 \right) = - 2$$

The composition of an oxy-acetylene flame for cutting of steel contain more oxygen.

Machinability of steels is improved by the addition of

In metal cutting $$BUE$$ formation results in