Pertanyaan

Jika 2 cos ( x + 4 π ) = cos ( x − 4 π ) , maka nilai cotan x = ...

Jika $2 cos (x + \frac{π}{4}) = cos (x - \frac{π}{4})$ , maka nilai $cotan x = ...$

I. Sutiawan

Master Teacher

Mahasiswa/Alumni Universitas Pasundan

Jawaban terverifikasi

Jawaban

nilai adalah .

nilai

table attributes columnalign right center left columnspacing 0px end attributes row blank blank cotan end table table attributes columnalign right center left columnspacing 0px end attributes row blank blank space end table table attributes columnalign right center left columnspacing 0px end attributes row blank blank x end table

adalah

Pembahasan

Ingat! Maka: , maka: Jadi, nilai adalah .

Ingat!

Maka:

, maka:

$begin mathsize 12px style table attributes columnalign right center left columnspacing 0px end attributes row cell 2 space cos open parentheses x plus straight pi over 4 close parentheses end cell equals cell cos open parentheses x minus straight pi over 4 close parentheses end cell row cell square root of 2 cos space x minus square root of 2 space sin space x end cell equals cell 1 half square root of 2 space cos space x plus 1 half square root of 2 space sin space x end cell row cell 2 space cos space x minus 2 sin space x end cell equals cell cos space x plus sin space x end cell row cell 2 space cos space x minus cos space x end cell equals cell sin space x plus 2 sin space x end cell row cell cos space x end cell equals cell 3 sin space x end cell row cell fraction numerator cos space x over denominator sin space x end fraction end cell equals 3 row cell cotan space x end cell equals 3 end table end style$

Jadi, nilai adalah .