Question

Fill in the blanks:
The sum of the AP, 1 + 2 +3 +4 +5 +6 + ---- 10 is​

Answer 1

Answer:

the sum

Sn =n/2(a+l)

=10/2(11)

=5(11)

=55

Answer 2

Answer:

AP,1+2+3+4+5+6------10

Step-by-step explanation:

1. a=1
2. d= 2-1 = 1
3. l =10

Tn=10

             Tn = a + (n-1)d

              10 = 1 + (n-1) 1

               10 -1 = (n-1)1   ( by multiplying 1 in n-1)

                9= n-1

                 9+1=n

                   10 = n

now , put the formula of sum

Sn = n/2(a+l)

Sn= 10/2(1+10)

Sn = 5(11)

Sn = 55.

hope its helps u ......