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# Core 2: Binomial expansion... help me ;-; watch

1. Can someone talk me through how to answer this binomial question?

A.) write down the binomial expansion of (1+x)^5
B.) Hence or otherwise express (1+x)^5 in the form p+q√3

I've answered part A and got 'x^5+ 5x^4 +10x^3 +10x^2 +5x +1' but I have no idea on how to do the next bit ;-;

Edit: Never mind I figured it out :3 Thanks anyway
2. (Original post by Mayora13)
Can someone talk me through how to answer this binomial question?

A.) write down the binomial expansion of (1+x)^5
B.) Hence or otherwise express (1+x)^5 in the form p+q√3

I've answered part A and got 'x^5+ 5x^4 +10x^3 +10x^2 +5x +1' but I have no idea on how to do the next bit ;-;
Are you sure you have posted the full/correct question for part b?

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3. (Original post by Mayora13)
Can someone talk me through how to answer this binomial question?

A.) write down the binomial expansion of (1+x)^5
B.) Hence or otherwise express (1+x)^5 in the form p+q√3

I've answered part A and got 'x^5+ 5x^4 +10x^3 +10x^2 +5x +1' but I have no idea on how to do the next bit ;-;
If you have done part À correctly then just factorise. I think you should have root3 as an irrational number (quotient) then multiply by Root three. Though The denominator Will be in a + broot3 then You need to multiply by a - broot3/a-broot3 to get The square of two differences for The same Numbers with a different sign.
4. (Original post by gdunne42)
Are you sure you have posted the full/correct question for part b?

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Ah I miswrote and misread the question...
B.) express (1-√3)^5 in the form p+q√3 where p and q are integers.
5. (Original post by Anfanny)
If you have done part À correctly then just factorise. I think you should have root3 as an irrational number (quotient) then multiply by Root three. Though The denominator Will be in a + broot3 then You need to multiply by a - broot3/a-broot3 to get The square of two differences for The same Numbers with a different sign.
Okay I'll try that then :3
6. (Original post by Mayora13)
Ah I miswrote and misread the question...
B.) express (1-√3)^5 in the form p+q√3 where p and q are integers.
So just substitute (-√3) for x in your binomial expansion and simplify the results

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