Question

write the nth term of -7,-11,-15,-19....

Answer 1

Given series : - 7,-11,-15,-19
From above a = - 7
d = t2 - t1
= - 11-(-7)
= - 11 + 7
= - 4
=) d = - 4
( for verification...
a3 = a + 2d = - 7 + 2(-4) = - 15
)
So an = a + nd = - 7 + n (-4) = - 7-4n