3 (2 X + 9 X + 3) (4 + X + 2)( 1 + + X X + 1) = 0TAN2+ ∈  E X C X...

1. 3 (2 x + 9 x + 3) (4 + x + 2)( 1 + + x x + 1) = 0

tan

2

+ ∈  

e

x

c x  π π 