Question

the 7th term of an ap is -4 and its 13th term is -16 . find the AP

Answer 1

Since given,
a+6d=-4.....{1}
Again,
a+12d=-16.....{2}
Subtracting {1}&{2}, we get:
d=-2
Now, putting the value of d in {1}, we get;
a=8
Thus required AP=a=8,a+d=6,a+2d=4.......

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