Roman C. answered • 11/17/12
Tutor
4.9
(642)
Masters of Education Graduate with Mathematics Expertise
Do you mean an = (-1)n * (n+1) ?
In that case, just plug in n=15.
a15 = (-1)15 * (15+1) = -1 * 16 = -16
Roman C.
tutor
a3 = (-1)3+153+1 = (-1)454 = 1*625 = 625
Now see if you can compute some other problems with calculating terms in sequences. These two examples should give you the enough of an idea. I assume these are from a textbook. Good Luck!
Report
11/17/12
Grace A.
Thanks! But would it not be -625?
Report
11/17/12
Grace A.
Yes, thanks so much!!
What about this one?
find the 3rd term in the sequence: an =(-1)n+15n+1
11/17/12