Question

Find the sum of the first 42 term of the AP, - 36 ; - 42 ; - 48 ; - 54 ........​

Answer 1

Answer:

ANSWER: - 6678

Step-by-step explanation:

Given, a= - 36 ; d= - 6

S(n) = n/2 ( 2a + (n - 1)d)

S(42) = 42/2 ( 2(-36) + (42-1)(-6))

» S(42) = 21 ( - 72 - 246)

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S(42) = - 6678