Terms for subject Mathematics containing as when

English	Russian
as is customary when	как это обычно делается
when a point moves parallel to the axis	когда точка движется параллельно осям координат ...
when at its greatest distance from the earth, Mars is about as bright as the polar star	при наибольшем удалении от
when the error goes to zero as fast as h2, we say that the difference formulas are second order accurate	порядка точности