Question

Sum of the first 10terms of Ap whose first term is 5 and common difference is also 5​

Answer 1

Answer:

in the pic bro!

Answer 2

sn = N/2( a + an )

s10 = 10 /2( 5 + a + ( n -1) 5

s10 = 5 ( 5 + 5 + 5 × 10- 5 )

s10 = 5 ( 5 + 50 )

s10 = 5 ( 55 )

s10 = 275

EXPLANATION :

here a = 5 d = 5 s10 = ?

we dont have an so I substitute the formula in an -----> 1 step

here n = 10 in sn so I substitute the all values in n