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Given that (AB = begin{pmatrix} 4 \ 3 end{pmatrix}) and (AC = begin{pmatrix} 2 \…

Given that (AB = begin{pmatrix} 4 \ 3 end{pmatrix}) and (AC = begin{pmatrix} 2 \ -3 end{pmatrix}), find |BC|.

  • A.
    (4sqrt{2})
  • B.
    (6sqrt{2})
  • C.
    (2sqrt{10})
  • D.
    (4sqrt{10})
Correct Answer: Option C
Explanation

(BC = BA + AC)

Given, (AB), then (BA = – AB)

= (AB = begin{pmatrix} 4 \ 3 end{pmatrix} implies BA = begin{pmatrix} -4 \ -3 end{pmatrix})

(therefore BC = begin{pmatrix} -4 \ -3 end{pmatrix} + begin{pmatrix} 2 \ -3 end{pmatrix})

= (begin{pmatrix} -2 \ -6 end{pmatrix})

(|BC| = sqrt{(-2)^{2} + (-6)^{2}} = sqrt{40} )

= (2sqrt{10})