Let 3A = 2, 3b = 5, let a and B denote the root of log (3) 30 Let 3A = 2, 3b = 5, try a and B to represent log3 √ 30

log3√30
=lg√30/lg3
=(1/2)(1+lg3)/lg3
3a=2,3b=5
∴lg3a=lg2,lg3b=lg5
lg3a+lg3b=1
2lg3+lgab=1
lg3=(1-lgab)/2
arcsinx-x
Original formula = (3-lgab) / (2-2lgab)

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