[SPAM] [obm-l] Trigonometria

[rejane@xxxxxxxxxxx]

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Estou com dificuldades para resolver essas duas questoes:

1) considere a função f(x) = arc cos (2x dividido por 1+x)
calcule F(pi sobre 2).

2) Resolva em R
tgx + tg2x - tg3x = 0

Obrigada.
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