Question

What is the explicit formula of the arithmetic sequence?
-9, -6, -3, 0....

Answer 1

Answer:An=-9+3(n-1)

Explanation:

First, find the common difference (the amount you are adding each time). You can find this by taking the second term and subtracting the first term. Now, identify the first term. This is the first number in your list. Finally, plug the first term in for A1 and the common difference in for d in the equation an=a1+d(n-1) Note: Leave the variable n as part of the equation.

Answer 2

Tn= -9+(n-1)×3

Explanation:

d= t2-t1 =t3-t2....

=-6-(-9)=3

We realize that this is an arithmetic sequence

Therefore Tn= a + (n-1)d, whereby a if the first term= - 9,d=3

Tn=-9+(n-1)×3