DEPARTMENT OF MATHEMATICS
MATH 1051
Problem Sheet 2 – 1st Semester , 2001-03-12
Questions marked * are to be handed directly to tutors by the end of the second tutorial
Italics correspond to Stewart 3rd edition
1. Stewart p.414: 11, 13, 15, 17 ( p.350: 7, 9, 11)
2. Stewart p.415: 23, 25, 27, 33 (p.351: 13, 15, 17)
3. Stewart p. 415: 35, 37, 43 (p.351: 19, 21, 23)
*4. Show that f(x) = x3 + x is 1 – 1 by three methods (a) graphically (b) calculus (c) algebra
(Hint: for (c) you may need the identity x2 + xy + y2 = (x + y/2)2 + 3/4y2 ).
*5. If f(x) = x/(x-1)and g(x) = x2 +1, find (fog)(x) and (gof)(x) and their domain and range.
*6. If f(x) = (x-1)/(x+1), find f -1(x) and the domain and range of f and f -1 and sketch them on the
same graph.