Question

find 'a' when 'd'= -3 , 'n' = 18 , an = -5 in ap

Answer 1

an= a + (n-1)d
-5= a + (18-1) -3
-5 = a + (17) -3
-5 =a -51
-5 +51 =a
46 =a

Answer 2

Answer:

a = -46

Step-by-step explanation:

GIVEN d=-3, an= -5 , n= 8

SO , SUM OF 18th TERM

IS a+17d

=> -5 = a + 17 * 3

SO. -5 +51 = a

SO. a= 46

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