Question

Write an equation to find the nth term of each sequence. Then find a24.
-1, -4, -7, -10

Answer 1

Answer:

Let an A.P start with a(first term) and have common difference d.

First term of A.P=a=a+(1-1)d

Second term of A.P= a+1d=a+(2-1)d

Third term of A.P=a+2d=a+(3-1)d

Fourth term of A.P=a+3d=a+(4-1)d

.

.

.

.

.

nth term of A.P=a+(n-1)d

Given a=(-1), d=a2-a1=(-4)-(-1)=(-3)

To find a24

a24=a+(24-1)d=a+23d

=(-1)+23*(-3)

=(-1)+(-69)

=(-70)