Question

Vektor a dan b membentuk sudut alpha, dengan sin alpha = 1/akar 7. Jika |vektor a| = akar 5 dan vektor a x vektor b = akar 30, maka vektor b x vektor b = ....?

Answer 1

Verified answer

Matematika SMA
Vektor

Pembahasan :
Misalkan alpha = β
Sin β = 1/(√7)
Cos β = (√6)/(√7)

a . b = √30

Ingat !
Bentuk ...
Vektor a . Vektor b = |a| |b| Cos β

Maka...
a . b = √30
|a| |b| cos β = 30
(√5) |b| (√6)/(√7) = √30
(√30)/(√7) |b| = √30
|b| = (√30) . (√7)/(√30)
|b| = √7


Maka...
b . b = |b|² = (√7)² = 7

Answer 2

Verified answer

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