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anonymous
 4 years ago
How do I simplify √21 / √2 + 1? The answer is 32√2. But I got 1.. D:
anonymous
 4 years ago
How do I simplify √21 / √2 + 1? The answer is 32√2. But I got 1.. D:

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anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0I tried: √2  1 √21 √2  1  =  x  √2 + 1 √2 + 1 √2  1

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0can u be clear \[\frac{\sqrt{21}}{\sqrt{2+1}}\] use conjugates \[\huge{\frac{\sqrt{21}}{\sqrt{2+1}}*\frac{\sqrt{21}}{\sqrt{21}} = \frac{(21)}{\sqrt{3}} = \frac{1}{\sqrt{3}}}\]

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0no it's just: √2  1 / √2 + 1

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0\[\huge\frac{\sqrt{21}}{\sqrt{21}}=1\]

Mimi_x3
 4 years ago
Best ResponseYou've already chosen the best response.0\[\large \frac{\sqrt{2}1}{\sqrt{2}+1} *\frac{\sqrt{2}1}{\sqrt{2}1} = \frac{(\sqrt{2}1)(\sqrt{2}1)}{21} = \frac{32\sqrt{2}}{1} =32\sqrt{2} \]

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0why is the denominator: 21?

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0and the denominator: 3  2√2?

EscherichiaRinku
 4 years ago
Best ResponseYou've already chosen the best response.2(a+b)(ab)=a^2+b^2

EscherichiaRinku
 4 years ago
Best ResponseYou've already chosen the best response.2and the nominator is (ab)(ab) = (ab)^2 expanded into a^22ab+b^2

Mimi_x3
 4 years ago
Best ResponseYou've already chosen the best response.0because \((\sqrt{a}+\sqrt{b})(\sqrt{a}\sqrt{b}) = a  b\)

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0ohh, thank you! I have to memorize those right?

Mimi_x3
 4 years ago
Best ResponseYou've already chosen the best response.0hm..if you want to lol. You can use FOIL to work it out anyway, might be harder; depends on you xD

EscherichiaRinku
 4 years ago
Best ResponseYou've already chosen the best response.2At school we were all forced to memorize such formulas, lol. Well, if you work on enough problems the simplification formulas will be intuitive :D

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0Mimi, how did you get 3  2√2/1? D:

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0'cause don't I have to multiply: √2*√2*√2*1?

Mimi_x3
 4 years ago
Best ResponseYou've already chosen the best response.0I used FOIL, to do it. Or you can use \[(\sqrt{a}\sqrt{b})^{2} = a2\sqrt{ab} +b\] I don't know what you are doing there, sorry.
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