Help
Have do I come from this \[\sqrt{n^2+nx}-1\] to this \[\Large \frac{\sqrt{1+\frac{x}n}-1}{\frac1n}\]
\[\sqrt{n ^{2}+nx}-1\]=\[\frac{ \sqrt{1+\frac{ x }{ n }}-\frac{ 1 }{ n }}{ \frac{ 1 }{ n } }\]
i don't see any way, because those 2 aren't equal
what souvik did is correct
you want to know how to get there ?
arrh I mean \[\sqrt{n^2+nx}-n\]
then what you wrote is correct
then you are right!
can you factor out n^2 from n^2+nx ?
no ? then, can you factor out n from n^2+nx first?
\[\sqrt{n*(n+x)}-n\]
no, thats incorrect, factor out 'n' from n+x
actually \(\sqrt{n*(n+x)}=\sqrt n \sqrt{n+x}\)
I cant spot the solution.. :(
you got this, right ?? \(\sqrt{n*(n+x)}=\sqrt n \sqrt{n+x}\) now n+x = n*1 + x/n * n = n (1+x/n) clear rtill here ?doubts ?
I can follow you until here: \[\sqrt{n^2+nx}-n=\sqrt{n*(n+x)}-n=\sqrt{n} \sqrt{n+x}-n\]
ok, can you distribute ? a (b+c) = ab+ac what about \(n \times (1+x/n) = ... ?\)
\[=n+x\]
so, i just replaced n+x by that quantity, by 'undistributing' or 'factoring' out the n
Yes so we have: \[\sqrt{n}\sqrt{n*(1+\frac{ x }{ n })}-n\]
\(n+x=(n\times 1+(x/n)\times n)=n(1+x/n)\)
yeah, \(\large \sqrt{n}\sqrt{n*(1+\frac{ x }{ n })}-n=\sqrt{n}\times \sqrt n\times \sqrt{(1+\frac{ x }{ n })}-n\) and \(\sqrt n \sqrt n=n\)
ok ?
\[\sqrt{n}\sqrt{n}\sqrt{1+\frac{ x }{ n }}-n=\frac{ \frac{ n*\sqrt{1+\frac{ x }{ n }}-n }{ n } }{ \frac{ 1 }{ n } }=\frac{ \sqrt{1+\frac{ x }{ n }}-1 }{ \frac{ 1 }{ n } }\]
you got it! :)
Thank you.
welcome ^_^
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