Pertanyaan

Diketahui vektor-vektor , dan sudut antara vektor dan adalah ….

Diketahui vektor-vektor begin mathsize 14px style straight a with rightwards arrow on top equals open parentheses table row 1 row 3 row 3 end table close parentheses comma space straight b with rightwards arrow on top equals open parentheses table row 3 row 2 row 1 end table close parentheses end style , dan sudut antara vektor dan adalah ….

S. Nur

Master Teacher

Jawaban terverifikasi

Jawaban

jawaban yang tepat adalah D.

Pembahasan

Untuk mengetahui besar sudutnya gunakan rumus Sehingga . Jadi, jawaban yang tepat adalah D.

Untuk mengetahui besar sudutnya gunakan rumus

$begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell cos invisible function application straight alpha end cell equals cell fraction numerator open parentheses straight a with rightwards arrow on top minus straight b with rightwards arrow on top close parentheses times open parentheses straight a with rightwards arrow on top plus straight c with rightwards arrow on top close parentheses over denominator open vertical bar straight a with rightwards arrow on top minus straight b with rightwards arrow on top close vertical bar open vertical bar straight a with rightwards arrow on top plus straight c with rightwards arrow on top close vertical bar end fraction end cell row cell cos invisible function application straight alpha end cell equals cell fraction numerator open parentheses table row cell negative 2 end cell row 1 row 2 end table close parentheses times open parentheses table row 2 row cell negative 2 end cell row 3 end table close parentheses over denominator square root of open parentheses negative 2 close parentheses squared plus 1 squared plus 2 squared end root times square root of 2 squared plus open parentheses negative 2 close parentheses squared plus 3 squared end root end fraction end cell row cell cos invisible function application straight alpha end cell equals cell fraction numerator negative 4 minus 2 plus 6 over denominator square root of 4 plus 1 plus 4 end root times square root of 4 plus 4 plus 9 end root end fraction end cell row cell cos invisible function application straight alpha end cell equals cell fraction numerator 0 over denominator square root of 9 times square root of 17 end fraction end cell row cell cos invisible function application straight alpha end cell equals 0 end table end style$

Sehingga .

Jadi, jawaban yang tepat adalah D.