Question

find S14 if a1 = 4 and d = 2.

Answer 1

Answer:

S14=n/2{2a+(n-1)d}

n=14

a=1

d=2

S14=14/2{2X1+(14-1)2}

. =7(2+13X2)

. =7(2+26)

. =7X28

. =196

S14=196