Solveeit Logo

Question

Question: If S<sub>n</sub> = np + \(\frac { 1 } { 2 }\) n(n – 1)Q where S<sub>n</sub> = sum of first n terms ...

If Sn = np + 12\frac { 1 } { 2 } n(n – 1)Q where Sn = sum of first n terms of an A.P. then common difference =

A

P + Q

B

2P + 3Q

C

2Q

D

Q

Answer

Q

Explanation

Solution

Sn = n2(a2)+n(pQ2)\mathrm { n } ^ { 2 } \cdot \left( \frac { \mathrm { a } } { 2 } \right) + \mathrm { n } \left( \mathrm { p } - \frac { \mathrm { Q } } { 2 } \right) ̃ C.d = 2×(Q2)2 \times \left( \frac { \mathrm { Q } } { 2 } \right) = Q