genxer123 wrote:
Madhavi1990 wrote:
You could simplify. 1.414(- 0.414) / 1.713(-0.713)
= -ve 0...6 (cause 4*4 =16)/ -ve 0.9 (0.3 *0.3= 0.009)--> 0.6/0.9(for simplicity)
--> 0.2/0.3 (-ve cancels out, direction is positive now)
--> approx 0.66 which is slightly more than 1/2 so closest value is B.
Please let me know if above method was right. Kudos please, if you like this solution!
Madhavi1990 , I like this solution, but I don't understand
1) how you got TO -.414, e.g.
You did not multiply by -1. That would have yielded \(\frac{2-\sqrt{2}}{3-\sqrt{3}}\approx{\frac{.59}{1.27}}\);
And 2) how you got from \(\frac{-.414}{-.713}\) to \(\frac{0.6}{0.9}\).
Maybe I'm slow on the uptake today. I don't understand your shorthand here, for example :
Quote:
1.414(- 0.414) / 1.713(-0.713)
= -ve 0...6 (cause 4*4 =16)/ -ve 0.9 (0.3 *0.3= 0.009)--> 0.6/0.9(for simplicity))
Would you please explain how you derived the first fraction, then how you got from the first fraction to the second? (And in steps with full words?)
Hi, apologies. I will be clearer from now on. I tried to use approximations based on powers and cyclicity. So 2^1 = ends in 2, 2^2 = 4, 2^3 = 8 and similiarly, for 4: 4^1 = 4, 4^2 = 16, 4^3 = 64. So the ending number matters. I don't know if this is the best solution, but it saved time for me,and seemed fine to apply as a theory
root 2(1-root2) = 1.414(1 - 1.414) = approximately with ending numbers 4*4 = 16 . So the number could be (negative) 0. (some number of zeroes) followed by 6. So I took -0.6 (as a possible approximation)
Root 3(1- root 3) = 1.73(1- 1.73) = 1.73 (-0.73) = approximately ending in 0...(some zeroes) 9 (3*3 = 9)
Then I combined the numerator/ denominator = 0.6/0.9 (it becomes positive now, as -ve cancels out) --> this is approximately 0.2/0.3 which 0.66 just a little more than half. B seemed suitable.
Please let me know if there are any errors conceptually or otherwise. Would love to know it, and hopefully not repeat the same error. Thank you!