The 4th term of an A.P.is 37 and the 6th term is 12 more than the 4th term.find the 1st and the 7th term of the sequence.
4th term is 37 ---> a + 3d = 37
6th term is 12 more than 4th term ---> a+5d = a+3d + 12
2d = 12
d = 6
then in a+3d = 37
a + 18 = 37
a = 19
first term is 19
7th term = a+6d = 127
check:
19 25 31 37 43 49
is 4th term 37 ? yes
is 6th term 12 more than 4th? yes
a+6d=19+36=55
Arithmetic and geometric progression. the following expression respresents a general arithmetic progression (AP):
A + (a + d ) + ( a + 2d) + :: + (1 - d) + 1