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Plz help me in finding 1•2+2•4+3•8+…n•2^n •=multiplication...:-)

Note by Prakher Gaushal 2 years, 7 months ago

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Sorry ,but I didn't have the patience to write it down in \(|LaTeX\) but couldn't let your doubt unattended , sohere's my solution .

P.S. If you find any mistakes, just tell me . I wrote the solution in a hurry !!! – Azhaghu Roopesh M · 2 years, 7 months ago

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@Azhaghu Roopesh M – Thanks – Prakher Gaushal · 1 year, 11 months ago

@Azhaghu Roopesh M – It think I told the same anyway nice to see your handwriting . Is this your backside of your project file? – U Z · 2 years, 7 months ago

@U Z – Yeah, correctly guessed :) – Azhaghu Roopesh M · 2 years, 7 months ago

@Azhaghu Roopesh M – Great.

Let me echo my comment in this note

\(\sum_{r=1}^{n} rx^r = \frac{x+(nx-n-1)x^{n+1}}{(x-1)^2}\)) is a useful formula to be aware of, to sum scenarios like this.

slide the series , and multiply it by 2 then take the difference , a g.p will be formed.next is easy – U Z · 2 years, 7 months ago

What is the sum for \( n = 1, 2, 3, 4, 5 \)? – Calvin Lin Staff · 2 years, 7 months ago

@Calvin Lin – Can't get what u want to say..... – Prakher Gaushal · 2 years, 7 months ago

@Prakher Gaushal – Sir wants to say write the genral term for the series that is and then put corresponding values for n – U Z · 2 years, 7 months ago

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## Comments

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TopNewestSorry ,but I didn't have the patience to write it down in \(|LaTeX\) but couldn't let your doubt unattended , sohere's my solution .

P.S. If you find any mistakes, just tell me . I wrote the solution in a hurry !!! – Azhaghu Roopesh M · 2 years, 7 months ago

Log in to reply

– Prakher Gaushal · 1 year, 11 months ago

ThanksLog in to reply

– U Z · 2 years, 7 months ago

It think I told the same anyway nice to see your handwriting . Is this your backside of your project file?Log in to reply

– Azhaghu Roopesh M · 2 years, 7 months ago

Yeah, correctly guessed :)Log in to reply

Let me echo my comment in this note

– Calvin Lin Staff · 2 years, 7 months agoLog in to reply

slide the series , and multiply it by 2 then take the difference , a g.p will be formed.next is easy – U Z · 2 years, 7 months ago

Log in to reply

What is the sum for \( n = 1, 2, 3, 4, 5 \)? – Calvin Lin Staff · 2 years, 7 months ago

Log in to reply

– Prakher Gaushal · 2 years, 7 months ago

Can't get what u want to say.....Log in to reply

– U Z · 2 years, 7 months ago

Sir wants to say write the genral term for the series that is and then put corresponding values for nLog in to reply