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(5+2root3)/(2+root3) can be written as 4-root3

User Mahesh Khond
by
2.7k points

1 Answer

28 votes
28 votes

Answer:

see explanation

Explanation:


(5+2√(3) )/(2+√(3) )

Rationalise the denominator by multiplying numerator/ denominator by the conjugate of the denominator.

the conjugate of 2 +
√(3) is 2 -
√(3) , then

=
((5+2√(3))(2-√(3)) )/((2+√(3))(2-√(3)) ) ← expand numerator/ denominator using FOIL

=
(10-5√(3)+4√(3)-6 )/(4-2√(3)+2√(3)-3 )

=
(4-√(3) )/(1)

= 4 -
√(3)

User Yuichi Araki
by
3.2k points
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