Mathematics

Question

Find u * v, if u= 12j and v = i + 5j
a (1,60)
b (0,60)
c -60
d 60

2 Answer

  • The correct answer for this problem would have to be D hope this helps:)
  • Answer:  The correct option is (d) 60.

    Step-by-step explanation:  We are given to find u * v, if the vectors u and v are defined as follows :

    [tex]u=12j,~~~v=i+5j.[/tex]

    We know that

    [tex]i.i=1,~~j.j=1,~~k.k=1,~~i.j=j.i=j.k=k.j=i.k=k.i=0.[/tex]

    So, we have

    [tex]u*v\\\\=(12j)*(i+5j)\\\\=12j.i+12j.5j\\\\=12\times 0+60\times 1\\\\=0+60\\\\=60.[/tex]

    Thus, the value of u * v is 60.

    Option (d) is CORRECT.

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