Question

Find the sum of the first 50 terms of an AP whose nth term is 3 -2n.
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Answer 1

Answer:

S50 = 1225

Step-by-step explanation:

n= 50

S50= ?

When n=1

t1 = 3- 2(1)

= 3- 2

= 1

t2 = 3- 2(2)

= 3-4

= - 1

a = 1

d = -1-1

d = -2

S50 = 50/2 ( 2(1)+(50-1) -2)

=25 (2+49-2)

= 25×49

= 1225