Solution: Do you want to use the cube sum formula A in this question? +b？ =(a+b)(a？ -ab+b？ )

Two sides x (1/2)+x (-1/2) = the square of 3.

x+2×x^( 1/2)×x^(- 1/2)+x^(- 1)=9

x+2+x^(- 1)=9

Both sides x+x (-1) = the square of 7.

x？ +2+x^(-2)=49

x？ +x^(-2)=47

x^(3/2)+x^(-3/2)=[x^( 1/2)]？ +[x^(- 1/2)]？

=[x^( 1/2)+x^(- 1/2)][x-x^( 1/2)×x^(- 1/2)+x^(- 1]

=[x^( 1/2)+x^(- 1/2)〕〔x+x^(- 1)- 1〕

=3×(7- 1)

=3×6

= 18

Original formula =( 18-3)/(47-2)

= 15/45

= 1/3