Question

Find the sum of first 15 terms of an A.P. whose n

th term is (3-2n).​

Answer 1

Step-by-step explanation:

please Mark has brainliest answer (❁´◡`❁)(♥_♥)(❁´◡`❁)(♥_♥)(❁´◡`❁)(♥_♥)

Answer 2

Step-by-step explanation:

1st term =a1= 3-2(1)=1

2nd term =3-2(2)=-1

3rd term=3-2(3)=-3..

so a=1, d= -1-1=-2 so S15= 15/2(2×1+(15-1)×-2

= 15/2(2-28)

=15/2(-26)

=15×-13=-195