We are asked to multiply two matrices. The first matrix is a $1 \times 2$ matrix $\begin{bmatrix} 1 & 2 \end{bmatrix}$ and the second matrix is a $2 \times 2$ matrix $\begin{bmatrix} 5 & 7 \\ 6 & 8 \end{bmatrix}$.

AlgebraMatrix MultiplicationLinear Algebra
2025/3/6

1. Problem Description

We are asked to multiply two matrices. The first matrix is a 1×21 \times 2 matrix [12]\begin{bmatrix} 1 & 2 \end{bmatrix} and the second matrix is a 2×22 \times 2 matrix [5768]\begin{bmatrix} 5 & 7 \\ 6 & 8 \end{bmatrix}.

2. Solution Steps

To multiply two matrices, the number of columns in the first matrix must be equal to the number of rows in the second matrix. In this case, the first matrix has 2 columns and the second matrix has 2 rows, so we can multiply them.
The result will be a 1×21 \times 2 matrix.
Let the first matrix be A=[12]A = \begin{bmatrix} 1 & 2 \end{bmatrix} and the second matrix be B=[5768]B = \begin{bmatrix} 5 & 7 \\ 6 & 8 \end{bmatrix}.
The resulting matrix C=A×BC = A \times B will have elements:
c11=(1)(5)+(2)(6)=5+12=17c_{11} = (1)(5) + (2)(6) = 5 + 12 = 17
c12=(1)(7)+(2)(8)=7+16=23c_{12} = (1)(7) + (2)(8) = 7 + 16 = 23
Therefore, C=[1723]C = \begin{bmatrix} 17 & 23 \end{bmatrix}.

3. Final Answer

[1723]\begin{bmatrix} 17 & 23 \end{bmatrix}

Related problems in "Algebra"

We are asked to solve four problems: (a) Expand and simplify the expression $6(2y-3) - 5(y+1)$. (b) ...

Algebraic SimplificationExponentsDifference of SquaresEquationsFactorization
2025/7/22

We are asked to simplify the expression $(a^{-2}b^3)^{-2}$, writing the answer with positive powers.

ExponentsSimplificationPower Rules
2025/7/22

A group of children bought a certain number of apples. If each apple is cut into 4 equal pieces and ...

System of EquationsWord Problem
2025/7/21

The problem asks to simplify the expression $\frac{x+1}{y} \div \frac{2(x+1)}{x}$.

Algebraic simplificationFractionsVariable expressions
2025/7/21

A group of children bought some apples. If each apple is divided into 4 equal pieces and 1 piece is ...

Linear EquationsSystems of EquationsWord Problem
2025/7/21

We need to find the value of the expression $6 + \log_b(\frac{1}{b^3}) + \log_b(\sqrt{b})$.

LogarithmsExponentsSimplification
2025/7/20

We need to solve the following equation for $y$: $\frac{y-1}{3} = \frac{2y+1}{5}$

Linear EquationsSolving EquationsAlgebraic Manipulation
2025/7/20

We are given the equation $\frac{3x}{2} = \frac{x-1}{7}$ and need to solve for $x$.

Linear EquationsSolving EquationsAlgebraic Manipulation
2025/7/20

The problem is to solve the equation $\frac{m}{5} = \frac{m+5}{10}$ for $m$.

Linear EquationsSolving EquationsVariables
2025/7/20

The problem is to solve the linear equation $\frac{2x}{5} = 3x + 1$ for $x$.

Linear EquationsEquation SolvingVariable Isolation
2025/7/20