Arithmatical - Surds and Indices

CATEGORY

11. If 2x = 3√32, then x is equal to
  A.   5
  B.   3
  C.  5/3
  D.  3/5
Solution
2x = 3√32= 2x
= (32)1/3
= (25)1/3
= 25/3
<=> x=5/3.
12. (0.04)-1.5 = ?
  A.  25
  B.  125
  C.  250
  D.  625
Solution
(0.04)-1.5 = (4/100)-1.5
= (1/25)-3/2
= (25)3/2
=(52)3/2
<=> 5(2x3/2)
= 53
= 125.
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