Simplify $\frac{2\sqrt[3]9}{1 + \sqrt[3]3 + \sqrt[3]9}.$ Thanks to anyone who helps!
\(\frac{2\sqrt[3]9}{1 + \sqrt[3]3 + \sqrt[3]9}\)
Note that
( 1)^3 - ( ∛3)^3 = ( 1 - ∛3 ) ( 1 + ∛3 + (∛3)^2) = ( 1 - ∛3 ) ( 1 - ∛3 + ∛9)
So this implies that if we multiply the numerator and denominator by ( 1 - ∛3) we get
2∛9 ( 1 - ∛3) 2 ∛9 - 2∛9 *∛3 2∛9 - 2∛27 2 [ ∛9 - 3 ]
__________________ = ______________ = ___________ = ___________ =
( 1 - ∛3 + ∛9) ( 1 - ∛3) (1)^3 - (∛3)^3 1 - 3 -2
- [ ∛9 - 3 ] =
3 - ∛9 [ = 3 - 3^(2/3) ]