The expression in the subject title of your question illustrates the first few terms of the binomial expansion (which has lots of uses in mathematics) - see https://en.wikipedia.org/wiki/Binomial_theorem for more information.
In the body of your question the solver has assumed you want to equate the left-hand side with the right-hand side and has assumed nx is a variable in its own right (it doesn't recognise implicit multiplication). Strangely, it has also assumed (1+x)n is also a single variable (!) and has solved the equation as if it were a quadratic.
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@@ End of Day Wrap Sun 28/6/15 Sydney, Australia Time 2:20pm ♪ ♫
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Tues 230/6/15
If you would like to comment on other site issues please do so on the Lantern Thread. Thank you.
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FTJ means 'For the juniors'
1) Funny pic I liked it anyway Thanks Awsomeee
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6) When are Farenheight and Celcius equal ? Thanks CPhill
7) Finding lowest common multiple FTJ+ Thanks Anonymous4338 and Melody
8) Goldbach's Conjecture Thanks CPhill
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