Write the first three terms of the series for which tn = 2(n+3). find the number of terms of the series required to make the sum 228.

The first three terms of the series are 8, 10 and 12. The number of terms is 12 to make the sum 228.

Step-by-step explanation:

The series is defined as

Put n=1.

Put n=2.

Put n=3.

The first three terms of the series are 8, 10 and 12.

It is an arithmetic series. The first terms is 8 and the common difference is

The sum of n terms of an arithmetic series is

Equate each factor equal to zero.

The number of terms can not be negative, therefore the value of n must be 12.

answear:

a

step-by-step explanation: a