17 Jan 2007 at 13:23 #1 demon8991 demon8991 Soldato Joined 7 Jan 2003 Posts 4,458 Location Gold Coast, Australia Got a question which i dont understand, well not so much i dont understand but that i actually dont know what its asking me to do. Find all complex numbers satisfying z^3 = -8
Got a question which i dont understand, well not so much i dont understand but that i actually dont know what its asking me to do. Find all complex numbers satisfying z^3 = -8
17 Jan 2007 at 13:56 #6 demon8991 demon8991 Soldato OP Joined 7 Jan 2003 Posts 4,458 Location Gold Coast, Australia Visage said: So take z^3+8 = 0 and divide both sides by (z+2). Then solve the resultant quadratic to get the other two roots. Click to expand... Why is it z^3+8?
Visage said: So take z^3+8 = 0 and divide both sides by (z+2). Then solve the resultant quadratic to get the other two roots. Click to expand... Why is it z^3+8?
17 Jan 2007 at 14:01 #8 demon8991 demon8991 Soldato OP Joined 7 Jan 2003 Posts 4,458 Location Gold Coast, Australia Ahhh sorry i misread thought the index was 3+8 thus being z^11 Sorry.
17 Jan 2007 at 14:35 #10 demon8991 demon8991 Soldato OP Joined 7 Jan 2003 Posts 4,458 Location Gold Coast, Australia Right im not getting this, doing it the way visage has said. Z^3+8 / z+2 = z^2-2z+4 but this does not solve. (-2+or- SQ of -12) / 2
Right im not getting this, doing it the way visage has said. Z^3+8 / z+2 = z^2-2z+4 but this does not solve. (-2+or- SQ of -12) / 2
17 Jan 2007 at 15:19 #12 demon8991 demon8991 Soldato OP Joined 7 Jan 2003 Posts 4,458 Location Gold Coast, Australia Ok ive never used imaginary numbers before. Thats the problem im having.
17 Jan 2007 at 15:33 #15 demon8991 demon8991 Soldato OP Joined 7 Jan 2003 Posts 4,458 Location Gold Coast, Australia Brilliant, thanks ever so much i get it now!
