Ques : A cyclic group of order 15 has an element x such that the set { x^3, x^5, x^9 } has exactly two elements.
The number of elements in the set { x^13n : n is a +ve integer} is
A) 3
B) 5
C) 8
D) 15
E) Inf.
ans is A
Please explain your ans. Thanks
enork wrote:If the group has order 15, then any element has order that divides 15, which immediately rules out x^3 = x^5 or x^5 = x^9.
Return to “Mathematics GRE Forum: The GRE Subject Test in Mathematics”
Users browsing this forum: No registered users and 3 guests