Β adalah sudut lancip tan β = 3/4 hitunglah : (i). tan 2β (ii) tan 4β

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Β adalah sudut lancip
tan β = 3/4
hitunglah :
(i). tan 2β
(ii) tan 4β

Jawaban Terkonfirmasi

Tan 2  beta = 2 tan  beta / 1 – (tan  beta * tan  beta )
tan 2  beta = 2 * 3/4 / 1-(3/4)²
tan 2  beta = 3/2 / 7/16
tan 2  beta = 24/7

tan 4  beta = tan 2 * 2  beta
= 2 x tan 2  beta / 1 – (tan 2  beta * tan 2  beta )
= 2 x 24/7 / 1 – (24/7)²
= 48/7 / -527/49
= 336/49 / -527/49
= -336/527

Semoga Membantu

Jawaban Terkonfirmasi

Karena β sudut lancip, maka tan bernilai positif

tan 2 beta = tan(beta + beta) \\ = frac{tan beta + tan beta}{1 - tan beta . tan beta} \\ = frac{2(tan beta)}{1 - tan ^{2} beta} \\ = frac{2(frac{3}{4})}{1 - (frac{3}{4})^{2}} \\ = frac{frac{6}{4}}{1 - frac{9}{16}} \\ = frac{frac{6}{4}}{frac{7}{16}} \\ = frac{frac{24}{16}}{frac{7}{16}} \\ boxed{boxed{bold{ = frac{24}{7} }}}

tan 4 beta = tan (2 beta + 2 beta ) \\ = frac{tan 2 beta + tan 2 beta}{1 - tan 2 beta . tan 2 beta} \\ = frac{2(tan 2 beta )}{1 - tan ^{2} 2 beta} \\ = frac{2(frac{24}{7})}{1 - (frac{24}{7})^{2}} \\ = frac{frac{48}{7}}{1 - frac{576}{49}} \\ = frac{frac{336}{49}}{frac{-527}{49}} \\ boxed{boxed{bold{= - frac{336}{527} }}}