1.         Determine limit(`+`(sqrt(`+`(`*`(`^`(x, 2)), ax)), `-`(sqrt(`+`(`*`(b, `*`(x)), `*`(`^`(x, 2)))))), x = infinity);  using the Explore Command 

limit(`+`(sqrt(`+`(`*`(a, `*`(x)), `*`(`^`(x, 2)))), `-`(sqrt(`+`(`*`(b, `*`(x)), `*`(`^`(x, 2)))))), x = infinity);

Embedded component

a; Embedded component

0

b; Embedded component

0