in an arithmetic sequence t sub 2=6 , t sub 6=16 find t sub 12
sorry i dont know how to do the sub thing.hopefully it makes sense.Thank you!
For an arithmetic sequence...
.
You're told that , so
and you're also told that , so
.
You now have 2 equations in 2 unknowns that you can solve simultaneously. Subtract equation 1 from equation 2 and you should find
.
Substitute back into equation 1 to get
.
Therefore .
What is ?