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nosnip
 one year ago
2(3+ sqrt(5)) / (3 sqrt(5))?
Express in the form b+c sqrt(5)
I got the answer 17 +3 sqrt5 but the correct answer is 7+3 sqrt 5?
nosnip
 one year ago
2(3+ sqrt(5)) / (3 sqrt(5))? Express in the form b+c sqrt(5) I got the answer 17 +3 sqrt5 but the correct answer is 7+3 sqrt 5?

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zepdrix
 one year ago
Best ResponseYou've already chosen the best response.1\[\large\rm \frac{2(3+\sqrt5)}{3\sqrt5}\color{royalblue}{\left(\frac{3+\sqrt5}{3+\sqrt5}\right)}=\frac{2(3+\sqrt5)^2}{3^2\sqrt5^2}\]

zepdrix
 one year ago
Best ResponseYou've already chosen the best response.1\[\large\rm =\frac{2(9+6\sqrt5+5)}{95}\]

zepdrix
 one year ago
Best ResponseYou've already chosen the best response.1\[\large\rm =\frac{2(14+6\sqrt5)}{4}\]

zepdrix
 one year ago
Best ResponseYou've already chosen the best response.1Maybe you can look at those steps and see where you made a boo boo :O

zepdrix
 one year ago
Best ResponseYou've already chosen the best response.1Hmm I'm not sure quite sure where you came up with 17 :o Would have to see your steps.

nosnip
 one year ago
Best ResponseYou've already chosen the best response.1I started by expanding the bracket in the numerator of the first fraction, so I had 6+2 sqrt(5) and multiplied this by 3+ sqrt(5) > Is this why I got the incorrect answer?

zepdrix
 one year ago
Best ResponseYou've already chosen the best response.1No, that should lead to the same result :)

zepdrix
 one year ago
Best ResponseYou've already chosen the best response.1\[\large\rm \frac{(6+2\sqrt5)(3+\sqrt5)}{4}=\frac{18+9\sqrt5+2\cdot5}{4}\]Is this what you got for the expansion on top?

zepdrix
 one year ago
Best ResponseYou've already chosen the best response.1Or was your bottom different maybe?

nosnip
 one year ago
Best ResponseYou've already chosen the best response.1For some reason I have 18+ 12 sqrt(5) +50 on top

nosnip
 one year ago
Best ResponseYou've already chosen the best response.1I did 6 x 3, then 6 x sqrt(5), then 3 x 2sqrt(5), then 5 x 2 sqrt 5

zepdrix
 one year ago
Best ResponseYou've already chosen the best response.1ya ya 12root5 in the middle, my bad! :) woops!

zepdrix
 one year ago
Best ResponseYou've already chosen the best response.1\[\large\rm \frac{(6+2\sqrt5)(3+\sqrt5)}{4}=\frac{18+12\sqrt5+2\cdot5}{4}\]

nosnip
 one year ago
Best ResponseYou've already chosen the best response.1What about the 2.5 at the end?

nosnip
 one year ago
Best ResponseYou've already chosen the best response.1shoudln't it be 10? as it is 2 x 5 (sqrt5)^5)

nosnip
 one year ago
Best ResponseYou've already chosen the best response.1Ohhh that was my mistake!

zepdrix
 one year ago
Best ResponseYou've already chosen the best response.1Yes, good :) I wrote 2*5, not 2.5. Hopefully that wasn't confusing.

zepdrix
 one year ago
Best ResponseYou've already chosen the best response.1Ya you did sqrt5*sqrt5 = 25. Silly little mistake there :D

nosnip
 one year ago
Best ResponseYou've already chosen the best response.1Thank you very much I understand :))
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