Question

find the third term of an arithmetic sequence with t2=9/2 and t5=6

Answer 1

there is a generic formula for these things:

an = a1 + d(n-1)

Answer 2

as such we can determine the missing parts with what weve got

assume t2 = t1 and t5 = t4 ; im used to using as and not ts, but that doesnt matter

Answer 3

as such:

t4 = t1 + d(3-1)

t4 = 9/2 + d(3-1)

6 = 9/2 + 2d ; solve for d

Answer 4

not 3-1; 4-1 :)

t4 = 9/2 + d(4-1)

6 = 9/2 + 3d ; solve for d

Answer 5

i got 4,5 but all my possible answers are singe digits

Answer 6

single*

Answer 7

4.5*

Answer 8

well

6 - 9/2 = 3d

3/2 = 3d

1/2 = d

t2 + 1/2 = t3

9/2 + 1/2 = 10/2 = 5

Answer 9

hm.... i calculated wrong...

Answer 10

what is the 5th term of arithmetic sequence if t2=-5 and t6=7

Answer 11

its the same concept, that is the beauty of generality; it works for any specific that you need to apply it to

Answer 12

hmm, it looks like we could also that arithmetic mean to do this with as well

t3 t4 t5 give us 3 terms to find; so difference divided by 4

7--5 = 12/4 = 3 for a common difference

t6 - d = t5

7-3 = 4 = t5, if i did that right

Answer 13

i think so. the answer is 4 then? cause that would fit my answer options

Answer 14

give it a shot:)

Answer 15

the only ones i got wrong were the ones i either did ask here or guessed to finish... lol, but i passes that one!

Answer 16

what are the first four terms of the geometric sequence with a t1=2 and tn=3tn-1