bonanova Posted November 6, 2010 Report Share Posted November 6, 2010 Don't blink or you'll miss it. 1. sqrt[-1] = sqrt[-1] 2. sqrt[-1/1] = sqrt[1/-1] 3. sqrt[-1]/sqrt[1] = sqrt[1]/sqrt[-1] 4. sqrt[-1] x sqrt[-1] = sqrt[1] x sqrt[1] 5. -1 = 1 [/code] You know the drill; prove me wrong. [/font] Quote Link to comment Share on other sites More sharing options...
0 Guest Posted November 6, 2010 Report Share Posted November 6, 2010 sqrt[-1]/sqrt[1] = i sqrt[1]/sqrt[-1] = -i 3. i = -i is false 5. -1 = 1 is therefore false Quote Link to comment Share on other sites More sharing options...
0 Guest Posted November 6, 2010 Report Share Posted November 6, 2010 (edited) sqrt[-1]/sqrt[1] = i sqrt[1]/sqrt[-1] = -i 3. i = -i is false 5. -1 = 1 is therefore false It is wrong, because sqrt[1]/sqrt[-1]=1/i, not -i!!! Edited November 6, 2010 by Balint Seregelyesi Quote Link to comment Share on other sites More sharing options...
0 Guest Posted November 6, 2010 Report Share Posted November 6, 2010 In the set of C (complex numbers) the sqrt(1)=1,-i. If you use -i as a root of 1 it will be clear that -1=-1, so the last step is wrong. Quote Link to comment Share on other sites More sharing options...
0 bonanova Posted November 6, 2010 Author Report Share Posted November 6, 2010 sqrt[1]/sqrt[-1]=1/i, not -i!!! Actually, they're the same. Let x = 1/i Multiply both sides by -i2, which is 1. x = -i Quote Link to comment Share on other sites More sharing options...
0 bonanova Posted November 6, 2010 Author Report Share Posted November 6, 2010 In the set of C (complex numbers) the sqrt(1)=1,-i. Not quite. sqrt[1] = 1 or -1. It's always real. Check your answer by squaring it. [-i]2 is not 1. Quote Link to comment Share on other sites More sharing options...
0 bonanova Posted November 6, 2010 Author Report Share Posted November 6, 2010 sqrt[-1]/sqrt[1] = i sqrt[1]/sqrt[-1] = -i 3. i = -i is false 5. -1 = 1 is therefore false If 3 is false, was it wrongly derived from 2? Or is 2 false also? Of the five statements, which is the last true one? Quote Link to comment Share on other sites More sharing options...
0 Guest Posted November 6, 2010 Report Share Posted November 6, 2010 The whole equation is wrong becouse none negative nubmer has a square root and it is easily proofable: Square root give us a number that if multiplied by itself, give us the number under the square root symbol so if the number we are looking for is possitive: + * + = + If the number is negative: - * - = + Conclusion:Negative numbers don't have square roots sqrt[-1] = false Quote Link to comment Share on other sites More sharing options...
0 Guest Posted November 6, 2010 Report Share Posted November 6, 2010 3 was wrongly derived from 2. 2. sqrt[-1/1] = sqrt[1/-1] 3. sqrt[-1]/sqrt[1] = sqrt[1]/sqrt[-1] therefore, sqrt[1/-1] = sqrt[1]/sqrt[-1], but if you run the equation you get i = 1/i. In other words... 2. i = i 3. i = 1/i then you can bring 3 to i*i = 1 and then -1 = 1. As a side note to Tsopi...sqrt[-1] is the imaginary number i. The squareroot of any negative number can be represent with use of the number i. Quote Link to comment Share on other sites More sharing options...
0 superprismatic Posted November 6, 2010 Report Share Posted November 6, 2010 Don't blink or you'll miss it. 1. sqrt[-1] = sqrt[-1] 2. sqrt[-1/1] = sqrt[1/-1] 3. sqrt[-1]/sqrt[1] = sqrt[1]/sqrt[-1] 4. sqrt[-1] x sqrt[-1] = sqrt[1] x sqrt[1] 5. -1 = 1 [/code] You know the drill; prove me wrong. [/font] I have a shorter version (don't even microblink): [code] 1. sqrt[-1] = sqrt[-1] 2. i = -i Quote Link to comment Share on other sites More sharing options...
0 araver Posted November 6, 2010 Report Share Posted November 6, 2010 1st and 2nd equations are valid as division is done before square rooting. The rule used to get the 3rd equation is "broken". The rule only applies to positive real numbers (and except division by zero). I have a shorter version (don't even microblink): 1. sqrt[-1] = sqrt[-1] 2. i = -i Nice microblink! Since we're breaking rules, it could get even more "real" than that, no need to be "complex" about it 1. sqrt[1] = sqrt[1] 2. 1 = -1 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted November 9, 2010 Report Share Posted November 9, 2010 Don't blink or you'll miss it. 1. sqrt[-1] = sqrt[-1] 2. sqrt[-1/1] = sqrt[1/-1] 3. sqrt[-1]/sqrt[1] = sqrt[1]/sqrt[-1] 4. sqrt[-1] x sqrt[-1] = sqrt[1] x sqrt[1] 5. -1 = 1 You know the drill; prove me wrong. 4-5 sqrt[1]=+-1; sqrt[-1]=+-i. 4.1 [+-i] x [+-i] = [+-1] x [+-1] 4.2 +-1 = +-1 Quote Link to comment Share on other sites More sharing options...
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bonanova
Don't blink or you'll miss it.
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