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Simplify root 4/3+root 7 by rationalizing the denominator​

1 Answer

6 votes

Answer:

6 - 2
√(7)

Explanation:

using the rule of radicals


√(a) ×
√(a) = a

given


(4)/(3+√(7) )

to rationalise the denominator , multiply the numerator and denominator by the conjugate of the denominator

the conjugate of 3 +
√(7) is 3 -
√(7) , then expression

=
(4(3-√(7)) )/((3+√(7))(3-√(7)) ) ← expand denominator using FOIL

=
(12-4√(7) )/(9-3√(7)+3√(7)-7 )

=
(12-4√(7) )/(2)

=
(12)/(2) -
(4√(7) )/(2)

= 6 - 2
√(7)

User Yizhar
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