Question

find the 19th term -11,-15,-19​

Answer 1

Given:-

A.P. = -11 , -15 , -19

To find:-

$t_{19}$ = ?

Solution:-

Let the first term. be a and common difference be d.

a = -11 and d = (-15+11) = -4

$= > t _{19} = - 11 + (19 - 1)( - 4) \\ = > t_{19} = - 11 + 18( - 4) \\ = > t_{19} = - 11 - 72 = - 83$

Hope its help uh❤

Answer 2

Answer:

A=-11

A1 =-15

A2=-19

..so here d =A1-À=-15-(-11)=-4

A19=a+d(n-1)

=-11+(-4(19-1)

=-11+(-76+4)

=-11+(-72)

=-11-72

=-83

so the 19th term of this ap is -83