Hi all

I want check my answer

Q 1 - Finif the sum of all integers between 1 and 100 inclusive ?

Answer :

firist tearm a1 = 1 d = 2

an = a1 + (n - 1 ) d

1 + ( n-1 )s = 100

n-1 = 99/2 = 48.5

then : S48.5 = 48.5/2 (2(1) + ( 48.5-1)2)

= 0.25

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Q2 : An object falling from rest in a vacuum near the surface of the Eath falls 16 feet during the first second , 48 feet during the second , 80 feet during the third second

How far will the object fall in t second ?

answer :

S16 = a1 + ( n-1 ) d

16 + ( 15 ) (32)

= 496