Please search before you post : https://www.beatthegmat.com/sqrt-2-sqrt- ... 50747.htmlimane81 wrote:Couldn't find the answer for this one... please help, thank you
√[2√63 + 2/(8+3√7)] =
A. 8 + 3√7
B. 4 + 3√7
C. 8
D. 4
E. √7
√[2√63 + 2/(8+3√7)] =
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ajith
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Always borrow money from a pessimist, he doesn't expect to be paid back.
Easy:
- Reduce the equation then factor out 2^4 (e.g. 2 to the 4th power) in the numerator = (2^4*3S-Root of 7 + 2^7)
- Now reduce by Factoring out 2^4 = 2^4*(3*S-Root 7 +2^3) / (3*S-Root of 7 +2^3)
- Cancel like terms from the numerator and demoninator [e.g. (3*S-Root of 7 + 2^3)]
- The residual term = 2^4
- Take the square root of 2^4 = S-Root of 16 = 4
ANSWER - D
If anyone needs help solving down to above from the original problem feel free to email me then I'll email you the scanned answer. This problem is difficult to explain with the characters on the typical typing keyboard because it does not have a square root symbol.
I will say this "When u come to a cross roads in a radical problem - FACTOR", which is the key to answering this problem.
- Reduce the equation then factor out 2^4 (e.g. 2 to the 4th power) in the numerator = (2^4*3S-Root of 7 + 2^7)
- Now reduce by Factoring out 2^4 = 2^4*(3*S-Root 7 +2^3) / (3*S-Root of 7 +2^3)
- Cancel like terms from the numerator and demoninator [e.g. (3*S-Root of 7 + 2^3)]
- The residual term = 2^4
- Take the square root of 2^4 = S-Root of 16 = 4
ANSWER - D
If anyone needs help solving down to above from the original problem feel free to email me then I'll email you the scanned answer. This problem is difficult to explain with the characters on the typical typing keyboard because it does not have a square root symbol.
I will say this "When u come to a cross roads in a radical problem - FACTOR", which is the key to answering this problem.
Last edited by frherndon on Tue Feb 09, 2010 3:58 pm, edited 2 times in total.
