Question

If tn is equal to 4+3n. Find the sum of n terms. ​

Answer 1

Explanation:

tn = a+(n-1) d

4 +3n = a + nd -d

4 = a +nd -d-3n

d = a + nd -4 -3n

a = -4 +nd -d -3n

Sn = n/2 [2a +(n-1) d]

use the formula And solve the problem

Answer 2

$\huge\boxed{Answer}$

Here , tn = An = 4 + 3n

then. A1 = a = 4 + 3 = 7

We know that Sum of the n terms -

Sn = n/2 { a + An }

= n/2 { 7 + 4 + 3n }

b. = n/2 (3n + 11)

= n(3n + 11)/2