Question

Which term of the ap 43,40,37 is the first negative term?

Answer 1

a=43
d=-3
AP=43+(n-1)(-3)
=43-3n+3
=46-3n
Now, we have to find the suitable value of n, so that the value of 46-3n is negative.
let us take n=14
nth term=46-3 (16)
=46-48
=-2
This is the first negative term of the series and it is the 16th term of the AP.
so, n=16