Matematika Sekolah Menengah Atas poin 10
mohon bantuannya kak​

poin 10
mohon bantuannya kak​

1) Bentuk perkalian dari matriks X adalah opsi A.

  [tex]X = \left[\begin{array}{cc}-5&8\\2&-3\end{array}\right] \left[\begin{array}{c}4\\5\end{array}\right] [/tex]

2) Matriks X yang memenuhi dari perkalian matriks tersebut adalah opsi C.

   [tex]X = \left[\begin{array}{c}\frac{1}{2}\\0\end{array}\right] [/tex]

Penjelasan dengan langkah-langkah

Sifat invers matriks.

  • AX = B ⇒ X = A⁻¹B
  • XA = B ⇒ X = BA⁻¹

Nomor 1

Diketahui

[tex]\left[\begin{array}{cc}3&8\\2&5\end{array}\right]X = \left[\begin{array}{c}4\\5\end{array}\right] [/tex]

Ditanyakan

Tentukan perkalian dari matriks X!

Jawab

Misal

[tex]B = \left[\begin{array}{c}4\\5\end{array}\right][/tex]

[tex]A = \left[\begin{array}{cc}3&8\\2&5\end{array}\right][/tex]

Invers dari matriks A.

[tex]A^{-1} = \frac{1}{15 - 16}\left[\begin{array}{cc}5&-8\\-2&3\end{array}\right][/tex]

[tex]A^{-1} = \frac{1}{-1}\left[\begin{array}{cc}5&-8\\-2&3\end{array}\right][/tex]

[tex]A^{-1} = \left[\begin{array}{cc}-5&8\\2&-3\end{array}\right][/tex]

Jadi

AX = B

  X = A⁻¹B

  [tex]X = \left[\begin{array}{cc}-5&8\\2&-3\end{array}\right] \left[\begin{array}{c}4\\5\end{array}\right] [/tex]

Jawaban A

Nomor 2

Diketahui

[tex]\left[\begin{array}{cc}6&10\\4&7\end{array}\right]X = \left[\begin{array}{c}3\\2\end{array}\right] [/tex]

Ditanyakan

Tentukan matriks X yang memenuhi!

Jawab

Misal

[tex]B = \left[\begin{array}{c}3\\2\end{array}\right][/tex]

[tex]A = \left[\begin{array}{cc}6&10\\4&7\end{array}\right][/tex]

Invers dari matriks A.

[tex]A^{-1} = \frac{1}{42 - 40}\left[\begin{array}{cc}7&-10\\-4&6\end{array}\right][/tex]

[tex]A^{-1} = \frac{1}{2}\left[\begin{array}{cc}7&-10\\-4&6\end{array}\right][/tex]

Jadi

AX = B

  X = A⁻¹B

  [tex]X = \frac{1}{2}\left[\begin{array}{cc}7&-10\\-4&6\end{array}\right]\left[\begin{array}{c}3\\2\end{array}\right] [/tex]

  [tex]X = \frac{1}{2} \left[\begin{array}{c}21-20\\-12+12\end{array}\right] [/tex]

  [tex]X = \frac{1}{2} \left[\begin{array}{c}1\\0\end{array}\right] [/tex]

  [tex]X = \left[\begin{array}{c}\frac{1}{2}\\0\end{array}\right] [/tex]

Jawaban C

Pelajari lebih lanjut  

Materi tentang matriks brainly.co.id/tugas/51941924

#BelajarBersamaBrainly #SPJ1

[answer.2.content]