find the sum of 4-1/n, 4-2/n, 4-3/n up to the nth term

I hope it will hlp uh

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Vnjgvv
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Chu chu
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the final answer is wrong i guess
 
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it is given as 7n-1/2 in my book
 
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6th step is wrong
=4n[-1/2(1+n)]
=4n-(1-n/2)
=8n-1-n/2
=7n-1/2
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Answer:
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Answer:

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Hey guys....it's a really nice question isn't it? And yes,the answer is 7n-1/2. Here's how I attempted it.

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If that picture isn't clear....

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3n2 - n is wrong. 

7n-1/2 is the right answer.
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Please view this image:

hope I helped!
 
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thanks
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a=4-1/n
d=-1/n
Sn=n/2(4-1/n + (n-1)-1/n)
    =n/2{2(4n -1) -n +1}
                 n
      
=n/2 {8n-2 -n +1}
                       n
      =n/2{7n - 1}
                n
       =n/2 * 7n -1
                      n
         =1/2[7n-1]
 
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7n-1/2
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This is the ans... I hope it will help u... Thank u :)

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(7n-1)÷2
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Here is the answer

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here is the answer to the above question

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 likhna nahi no. 4. likna nahi aata nahi aur uper se hume confuse kararha hai
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Hlo this is the correct answer

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7n-1/2 is the correct answer.......
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a=4-1/n
d=a2-a1
  =-1/n
therefore , on putting these values in the formula.....
  Sn=n/2[2a+{n-1}d]
on solving further.....
we get,....
     Sn=7n-1/2
                  HOPE THIS HINT HELPS !!
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I hope it will help you

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