Question

An ap has commondifference 2,sum of first n terms 49 and 7 term is 13 the value of n

Answer 1

Answer:

Step-by-step explanation:

d=2

Sn= 49

a7=13

a+6d=13

a+6[2]=13

a+12=13

a=1

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

49 = n/2[2*1+[n-1] 2]

98= n[2+2n-2]

98=n[2n]

98= 2n2

49=n2

n=7