Sequences and Summations (1)

kashifzaidi · #1 $Old$ November 4th, 2009, 04:27 PM

Just want to verify my answers, if there are wrong answers then plz help me.

1) Give the first 4 terms of the following sequences
(indices begin at 0; you need not multiply everything out):

a) {An} = (-2)^n

b) {An} = 3

c) {An} = 7 + 4^n

d) {An} = 2^n + (-2)^n

My answers:

a) 1,-2,4,-8
b) 3
c) 1,11,23,71
d) 2,0,8,0

Defunkt · #2 $Old$ November 4th, 2009, 04:42 PM

Quote:

Originally Posted by kashifzaidi $View Post$

Just want to verify my answers, if there are wrong answers then plz help me.

1) Give the first 4 terms of the following sequences
(indices begin at 0; you need not multiply everything out):

a) {An} = (-2)^n

b) {An} = 3

c) {An} = 7 + 4^n

d) {An} = 2^n + (-2)^n

My answers:

a) 1,-2,4,-8
b) 3
c) 1,11,23,71
d) 2,0,8,0

b) should be 3,3,3,3

for c), how much is $7+4^0$ ? Definitely not 1! The other terms are correct though, and so are a) and d).