Question

dado sen x = 2/3 e cos x = - √5/3, obtenha a) tg 2x

Answer 1

Olá Geovana

sen(x) = 2/3
cos(x) = -√5/3

sen(2x) = 2sen(x)*cos(x) = -4√5/9 

cos(2x) = cos²(x) - sen²(x)
cos(2x) = 5/9 - 4/9 = 1/9 

tg(2x) = sen(2x)/cos(2x) = (-4√5/9)/(1/9) = -4√5

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