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Did i rationalize this correctly?

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Original post by Zacken
As above - (I have no clue how this slipped my eye) but the correct answer should be 5(12)1=5521=525\frac{5(1 - \sqrt{2})}{-1} = \frac{5 - 5\sqrt{2}}{-1} = 5\sqrt{2} - 5, i.e: you need to multiply out the 5(12)5(1-\sqrt{2}) as 5525 - 5\sqrt{2} and not as 525 - \sqrt{2}.
Phewww, so I was right!
Reply 21
Original post by phat-chewbacca
Phewww, so I was right!


Yeah, just me being dumb again :lol:
Original post by Zacken
Yeah, just me being dumb again :lol:
It happens to everyone! I was just wondering do you have the PiXL GCSE Maths Predicted Paper 2016?
Reply 23
Original post by phat-chewbacca
It happens to everyone! I was just wondering do you have the PiXL GCSE Maths Predicted Paper 2016?


Unfortunately not, sorry!
Original post by Zacken
Unfortunately not, sorry!
No worries, thanks anyway!
Original post by Zacken
As above - (I have no clue how this slipped my eye) but the correct answer should be 5(12)1=5521=525\frac{5(1 - \sqrt{2})}{-1} = \frac{5 - 5\sqrt{2}}{-1} = 5\sqrt{2} - 5, i.e: you need to multiply out the 5(12)5(1-\sqrt{2}) as 5525 - 5\sqrt{2} and not as 525 - \sqrt{2}.



http://prntscr.com/axdbp4 ?

urmm so why don't we multiply the two denominators?
Original post by phat-chewbacca
No worries, thanks anyway!


http://www.mathsgenie.co.uk/resources/june2016p1.pdf

That what you looking for?

Sorry if its not
Reply 27
Original post by junayd1998
http://prntscr.com/axdbp4 ?

urmm so why don't we multiply the two denominators?


You do multiply the two denominators. Your denominators were fine in the previous screenshot. Your numerator wasn't.
Original post by Zacken
You do multiply the two denominators. Your denominators were fine in the previous screenshot. Your numerator wasn't.


http://prntscr.com/axdy3h So that's the final answer?
Reply 29
Original post by junayd1998
http://prntscr.com/axdy3h So that's the final answer?


Indeed.
Here is the right answer. https://gyazo.com/31ec0ada59c65f931222e056a681f538
It said rationalise the denominator so you probably dont need to do the final step

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