Simplify
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- gmat740
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It is a simple rationalisation problem
in the denominator you are given : 2-sqrt(3)
try to make it as integer:
best possible way => multiply with conjugate = 2+sqrt(3)
so, we have denominator as,
[2+sqrt(3)]*[2-sqrt(3)]
this is in the form of
(a+b)(a-b) = a^2 - b^2 = 2^2-(sqrt 3)^2 = 4-3 =1
but we have multiplied denominator,so to balance that effect of multiplication,we need to multiply the numerator as well with the same multiple
so,
3(2-sqrt3)
this has to be the answer
You can further solve this as
6 - 3*sqrt(3)
Hope this helps
in the denominator you are given : 2-sqrt(3)
try to make it as integer:
best possible way => multiply with conjugate = 2+sqrt(3)
so, we have denominator as,
[2+sqrt(3)]*[2-sqrt(3)]
this is in the form of
(a+b)(a-b) = a^2 - b^2 = 2^2-(sqrt 3)^2 = 4-3 =1
but we have multiplied denominator,so to balance that effect of multiplication,we need to multiply the numerator as well with the same multiple
so,
3(2-sqrt3)
this has to be the answer
You can further solve this as
6 - 3*sqrt(3)
Hope this helps












