Problem: If a,b, and c are positive integers, the radicals a+cb and acb are equal when and only when.
Answer Choices:
A. a=b=c=1
B. a=b and c=a=1
C. c=ab(a2−1)
D. a=b and c is any value
E. a=b and c=a−1
Solution:
If a+cb=acb then a+cb=a2cb.
∴ac=b(a2−1);∴c=o(a2−1)/a.