show that if f: R2 - R is continuous, then the map g: R2 - R given by g(a, () = f(x + y, x - y) is continuous.Let f: R2 ) R be continuous. Then show that the map 50:1122 } 1R given by 9206,31) == f(m+y.m y) is also continuous. If f is uniformly continuous, will 99 also be uniformly continuous as well