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  1. If  
    4√3 + 5√2
    = a + b√6,   then the values of a and b are respectively
    48 + √18
    1. 9
      , −
      4
      1515
    2. 3
      ,
      4
      1133
    3. 9
      ,
      2
      105
    4. 3
      ,
      4
      515
Correct Option: D

L.H.S. =
4√3 + 5√2
48 + √18

=
4√3 + 5√2
4√3 + 3√2

=
4√3 + 5√2
×
4√3 − 3√2
4√3 + 3√24√3 − 3√2

(Rationalising the denominator)
=
16 × 3 − 12 √6 + 20√6 −15 × 2
(4√3)2 − (3√2)2

=
48 + 8√6 − 30
48 − 18

=
18 + 8√6
=
9
+
4√6
301515

=
3
+
4√6
515

Now, 
3
+
4√6
= a + b√6
515

∴  a =
3
and b =
4
515



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