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anonymous
 5 years ago
x^3 2x^2+13x=0 leave in exact form no decimals approx
anonymous
 5 years ago
x^3 2x^2+13x=0 leave in exact form no decimals approx

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You could write the same equation as: x(x^2  2x + 13) = 0 so one root is x = 0 and the others are the roots of x^2  2x + 13 =0 equation which are (1  2sqrt3) i and (1 + 2sqrt3 i)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0did you solved this using quadratic formula negative b + or  square root b^2  4ac over 2a?

radar
 5 years ago
Best ResponseYou've already chosen the best response.0I believe he did and he simplified the answer.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i tried that i did broke it down i got 2+ or  sqrt48 over 2 times "a" which is 2 but when you divide the top (2+ or  sqrt48) i got 24 which breaks down to to 2i sqrt 6 how did he get the 3?

radar
 5 years ago
Best ResponseYou've already chosen the best response.0\[\sqrt{48}=\sqrt{16\times3}\]

radar
 5 years ago
Best ResponseYou've already chosen the best response.0\[\sqrt{16}\times \sqrt{3}\]\[4\sqrt{3}\]

radar
 5 years ago
Best ResponseYou've already chosen the best response.0does that simplification rings a bell?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yeah i get it now its hard when someone just leaps from one spot to another

radar
 5 years ago
Best ResponseYou've already chosen the best response.0I haven't double checked but nikola usually gets it right. Good luck

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Sweets, http://en.wikipedia.org/wiki/Quadratic_equation a=1 b=(2) c=13 b^2  4ac = (2)^2  4*1*13 = 48 which is smaller than 0,so roots are complex and can be calculated as : b/2a + (sqrt [ (b^2  4ac)] /2a)*i b/2a  (sqrt [ (b^2  4ac)] /2a)*i

radar
 5 years ago
Best ResponseYou've already chosen the best response.0And I have to agree with you sometimes simplified looks more complicated lol\[\sqrt{48}=4\sqrt{3}\] doesn't look to much more simple Hi

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.02+(sqrt[2^24(1)(13)]/2(1) = 2+(sqrt[48])/2 = so do I divide out the 2 from the bottom like so or no lol sorry for all this... 1+(sqrt[24] then you break down the 24 to 4i sqrt 6

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so 1+\[4i \sqrt{6} and 14i \sqrt{6}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0that was suppose to be 2i sqrt6 not the 4 my bad

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Sweets, a=1 b=(2) c = 13 b^2  4ac = (2)^2  4*1*13 = 48 < 0 so; b/2a + (sqrt [ (b^2  4ac)] /2a)*i b = (2) = 2 so b/2a is 2/2*1 =1 sqrt [ [b^2  4ac) ] = sqrt [(48)] = sqrt48 which is 4sqrt3 (sqrt [ (b^2  4ac)] /2a)*i is 4sqrt3 / 2 *1 = 2sqrt3 I hope this helps.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i have got 2+24i and 224i as the answer

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yes thats correct nikola:)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Sweets,it s b/2*a not b/a :)

radar
 5 years ago
Best ResponseYou've already chosen the best response.0\[((2)\pm \sqrt{(2)^{2}(4)(1)(13)})/2\]\[(2\pm \sqrt{452})/2\]\[(2\pm \sqrt{48})/2\] can you take it from there?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Oooooo lol i see i see

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0you miss one thing it messes it all up lol

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yeah...thats what math is all about:)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so th eanswer probably is 1+24i & 124i if i am not wrong:)

radar
 5 years ago
Best ResponseYou've already chosen the best response.0Continuing on.\[(2\pm(\sqrt{16\times3})/2\] \[(2\pm(\sqrt{16}\sqrt{3})/2\]\[(2\pm(4\sqrt{3})/2\] now do the division\[1\pm2\sqrt{3}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0how did u get 3 there? under the root???

radar
 5 years ago
Best ResponseYou've already chosen the best response.0I would leave it there are you could go further and do this. Convert the radical as follows:\[\sqrt{3}=\sqrt{3 X1}\]

radar
 5 years ago
Best ResponseYou've already chosen the best response.0The square root of 1 is the imaginary operator i so the final answer becomes:\[1\pm \sqrt{3}i\]

radar
 5 years ago
Best ResponseYou've already chosen the best response.0Did you understand I was trying to show in the radical 3 times a 1 ? and i left out the 2 so it should be\[1\pm2\sqrt{3}i\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yeah i seen what you did 4 squared times 3 is 48 but you had to divide the 4 by 2 i get it

radar
 5 years ago
Best ResponseYou've already chosen the best response.0Yeahh!!!Now practice is the key. Notice that they did not want you to really get the value no decimals etc. so that is as far as you need to take it.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0lol thank all of you so much. Im not as slow as i seem this was just a total brain fart

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Im a visual learner so it helped when you showed :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0you're welcome sweets,good luck with your studies.
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