Pertanyaan

Nilai dari cos 84° - sin 84° tan 48° adalah ....

-1
cos 132°
0
cos 48°
1

M. Robo

Master Teacher

Jawaban terverifikasi

Pembahasan

Perhatikan bahwa Sehingga Karena ,maka Perhatikan bahwa 132° = 180° - 48° dan .Sehingga

Perhatikan bahwa

$begin mathsize 14px style tan invisible function application x equals fraction numerator sin invisible function application x over denominator cos invisible function application x end fraction end style$

Sehingga

$begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell cos invisible function application 84 degree minus sin invisible function application 84 degree tan invisible function application 48 degree end cell equals cell cos invisible function application 84 degree minus sin invisible function application 84 degree times fraction numerator sin invisible function application 48 degree over denominator cos invisible function application 48 degree end fraction end cell row blank equals cell fraction numerator cos invisible function application 84 degree times cos invisible function application 48 degree over denominator cos invisible function application 48 degree end fraction minus fraction numerator sin invisible function application 84 degree times sin invisible function application 48 degree over denominator cos invisible function application 48 degree end fraction end cell row blank equals cell fraction numerator cos invisible function application 84 degree times cos invisible function application 48 degree minus sin invisible function application 84 degree times sin invisible function application 48 degree over denominator cos invisible function application 48 degree end fraction end cell end table end style$

Karena , maka

$begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell cos invisible function application 84 degree minus sin invisible function application 84 degree tan invisible function application 48 degree end cell equals cell fraction numerator cos invisible function application 84 degree times cos invisible function application 48 degree minus sin invisible function application 84 degree times sin invisible function application 48 degree over denominator cos invisible function application 48 degree end fraction end cell row blank equals cell fraction numerator cos invisible function application open parentheses 84 degree plus 48 degree close parentheses over denominator cos invisible function application 48 degree end fraction end cell row blank equals cell fraction numerator cos invisible function application 132 degree over denominator cos invisible function application 48 degree end fraction end cell end table end style$

Perhatikan bahwa 132° = 180° - 48° dan . Sehingga

$begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell cos invisible function application 84 degree minus sin invisible function application 84 degree tan invisible function application 48 degree end cell equals cell fraction numerator cos invisible function application 132 degree over denominator cos invisible function application 48 degree end fraction end cell row blank equals cell fraction numerator cos invisible function application open parentheses 180 degree minus 48 degree close parentheses over denominator cos invisible function application 48 degree end fraction end cell row blank equals cell fraction numerator negative cos invisible function application 48 degree over denominator cos invisible function application 48 degree end fraction end cell row blank equals cell negative 1 end cell row blank blank blank end table end style$