Respuesta :

Answer:

5.5

Step-by-step explanation:

tana=3a=3tana-tana^3a/1-3 tana^2a

=3(1/2)-(1/2)^3/1-3(1/2)^2

=3/2-1/8 /1-3/4

=(12-1/8)/1/4)

=(11/8)/(1/4)

=11/8×4

11/2====5.5

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