Pertanyaan

Diketahui , makasudut antara a dan b adalah ....

Diketahui , maka sudut antara $a$ dan $b$ adalah ....

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S. Nur

Master Teacher

Jawaban terverifikasi

Jawaban

jawaban yang tepat adalah B.

Pembahasan

Perhatikan bahwa Jadi, didapat . Jadi, jawaban yang tepat adalah B.

Perhatikan bahwa

$begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell open vertical bar straight a with rightwards arrow on top plus straight b with rightwards arrow on top close vertical bar end cell equals cell square root of 5 end cell row cell open vertical bar straight a with rightwards arrow on top plus straight b with rightwards arrow on top close vertical bar squared end cell equals cell open parentheses square root of 5 close parentheses squared end cell row cell open parentheses straight a with rightwards arrow on top plus straight b with rightwards arrow on top close parentheses bullet open parentheses straight a with rightwards arrow on top plus straight b with rightwards arrow on top close parentheses end cell equals 5 row cell straight a with rightwards arrow on top bullet straight a with rightwards arrow on top plus straight a with rightwards arrow on top bullet straight b with rightwards arrow on top plus straight b with rightwards arrow on top bullet straight a with rightwards arrow on top plus straight b with rightwards arrow on top bullet straight b with rightwards arrow on top end cell equals 5 row cell open vertical bar straight a with rightwards arrow on top close vertical bar squared plus 2 straight a with rightwards arrow on top bullet straight b with rightwards arrow on top plus open vertical bar straight b with rightwards arrow on top close vertical bar squared end cell equals 5 row cell open vertical bar straight a with rightwards arrow on top close vertical bar squared plus 2 open vertical bar straight a with rightwards arrow on top close vertical bar open vertical bar straight b with rightwards arrow on top close vertical bar cos invisible function application straight angle open parentheses straight a with rightwards arrow on top comma straight b with rightwards arrow on top close parentheses plus open vertical bar straight b with rightwards arrow on top close vertical bar squared end cell equals 5 row cell open parentheses square root of 2 close parentheses squared plus 2 open parentheses square root of 2 close parentheses open parentheses 3 close parentheses cos invisible function application straight angle open parentheses straight a with rightwards arrow on top comma straight b with rightwards arrow on top close parentheses plus open parentheses 3 close parentheses squared end cell equals 5 row cell 2 plus 6 square root of 2 cos invisible function application straight angle open parentheses straight a with rightwards arrow on top comma straight b with rightwards arrow on top close parentheses plus 9 end cell equals 5 row cell 6 square root of 2 cos invisible function application straight angle open parentheses straight a with rightwards arrow on top comma straight b with rightwards arrow on top close parentheses plus 11 end cell equals 5 row cell 6 square root of 2 cos invisible function application straight angle open parentheses straight a with rightwards arrow on top comma straight b with rightwards arrow on top close parentheses end cell equals cell negative 6 end cell row cell cos invisible function application straight angle open parentheses straight a with rightwards arrow on top comma straight b with rightwards arrow on top close parentheses end cell equals cell fraction numerator negative 6 over denominator 6 square root of 2 end fraction end cell row cell cos invisible function application straight angle open parentheses straight a with rightwards arrow on top comma straight b with rightwards arrow on top close parentheses end cell equals cell negative 1 half square root of 2 end cell end table end style$

Jadi, didapat .

Jadi, jawaban yang tepat adalah B.