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Barrelracing
 one year ago
Rationalize the denominator of square root of negative four over open parentheses 7 minus 3 i close parentheses plus open parentheses 2 plus 5 i.
Barrelracing
 one year ago
Rationalize the denominator of square root of negative four over open parentheses 7 minus 3 i close parentheses plus open parentheses 2 plus 5 i.

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Barrelracing
 one year ago
Best ResponseYou've already chosen the best response.0dw:1437857496870:dw

carolinar7
 one year ago
Best ResponseYou've already chosen the best response.0dw:1437846970791:dw

carolinar7
 one year ago
Best ResponseYou've already chosen the best response.0dw:1437847013934:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1437846985513:dw

carolinar7
 one year ago
Best ResponseYou've already chosen the best response.0No you need to multiply it by conjugate

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0the first thing you have to do is combine the denominator into one complex number. dw:1437847204733:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1437847105860:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0that's (7 + 2) + (3i + 5i)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.09 + 2i, so now you have \[\frac{ \sqrt{4} }{ 9+2i }\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0can you write √4 in terms of i?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[\sqrt{4}=\sqrt{4} \times \sqrt{1}=2i\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0^do you understand that?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so now we have \[\frac{ 2i }{ 9+2i }\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0and now you can multiply by the conjugate like @carolinar7 said above

Barrelracing
 one year ago
Best ResponseYou've already chosen the best response.0ok I don't know how to do that

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0to find the conjugate change the sign of the imaginary part of the denominator. → 92i Then multiply the numerator and denominator by it. \[\frac{ 2i(92i) }{ (9+2i)(92i) }\] Distribute/foil and the i's will cancel in the denominator

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0You had this at some point \[\frac{ 18i4i^2 }{ 814i^2 }\] Remember that i² = 1, so you'll have \[\frac{ 4+18i }{ 85 }\]
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