which term of 79, 77, .....is -40.
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Verified answer
ho ho ho
a = 79
d = a2-a1 = 79-77 = -2
an = -40
an = a+(n-1)×d
-40 = 79+(n-1)×-2
-40 = 79+(-2n+2)
-40 = 81-2n
-40-81 = -2n
-121=-2n
+121/2,=n
hey mate I have one doubt is it 47 or 40
here a =79
d = -2
an = a+(n-1)d
47 = 79 - 2n +2
47 - 81 = -2n
-34 = -2n
n =34/2
n =17
Hence 17th term of AP is 47