Bab 15 Matriks

Posted on April 30, 2016 by user

4.9 SPM Practis (Soalan Pendek)

Soalan 1:

(\begin{matrix} 1 & 4 \\ 6 & 2 \end{matrix}) + 3 (\begin{matrix} 2 & 0 \\ 4 & - 3 \end{matrix}) - (\begin{matrix} - 3 & 0 \\ - 2 & - 5 \end{matrix}) =

Penyelesaian:

\begin{array}{l} (\begin{matrix} 1 & 4 \\ 6 & 2 \end{matrix}) + 3 (\begin{matrix} 2 & 0 \\ 4 & - 3 \end{matrix}) - (\begin{matrix} - 3 & 0 \\ - 2 & - 5 \end{matrix}) \\ = (\begin{matrix} 1 & 4 \\ 6 & 2 \end{matrix}) + (\begin{matrix} 6 & 0 \\ 12 & - 9 \end{matrix}) - (\begin{matrix} - 3 & 0 \\ - 2 & - 5 \end{matrix}) \\ = (\begin{matrix} 7 & 4 \\ 18 & - 7 \end{matrix}) - (\begin{matrix} - 3 & 0 \\ - 2 & - 5 \end{matrix}) \\ = (\begin{matrix} 7 - (- 3) & 4 - 0 \\ 18 - (- 2) & - 7 - (- 5) \end{matrix}) \\ = (\begin{matrix} 10 & 4 \\ 20 & - 2 \end{matrix}) \end{array}

Soalan 2:

Cari nilai mdalam persamaan matriks berikut:

(\begin{matrix} 9 & - 4 \\ 5 & 0 \end{matrix}) + \frac{1}{2} (\begin{matrix} 8 & m \\ 6 & - 10 \end{matrix}) = (\begin{matrix} 13 & - 7 \\ - 2 & 1 \end{matrix})

Penyelesaian:

\begin{array}{l} (\begin{matrix} 9 & - 4 \\ 5 & 0 \end{matrix}) + \frac{1}{2} (\begin{matrix} 8 & m \\ 6 & - 10 \end{matrix}) = (\begin{matrix} 13 & - 7 \\ - 2 & 1 \end{matrix}) \\ - 4 + \frac{1}{2} m = - 7 \\ \frac{1}{2} m = - 3 \\ m = - 6 \end{array}

Soalan 3:

\begin{array}{l} Diberi \\ (\begin{array}{l} 2 x \\ 3 y \end{array}) - 4 (\begin{array}{l} - 2 \\ 3 \end{array}) = (\begin{array}{l} - 2 \\ 6 \end{array}) \\ Cari nilai x dan y . \end{array}

Penyelesaian:

2x + 8 = –2

2x = –10

x= –5

3y – 12 = 6

3y = 18

y= 6

Soalan 4:

Diberi bahawa persamaan matriks 3(6 m) + n(3 4) = (12 7),

Cari nilai m+ n.

Penyelesaian:

3(6 m) + n(3 4) = (12 7)

18 + 3n = 12

3n = –6

n= –2

3m + 4n = 7

3m + 4(–2) = 7

3m = 15

m= 5

Maka m + n = 5 + (–2) = 3