If the solution for the system of equations x | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) The system of equations can be written in matrix form $AX=B$ as: $\left[\begin{array}{ccc}1 & 2 & -1 \ 3 & -1 & 2 \ 2 & -2 & 3\end{array}ight]

Vedclass · Accepted Answer

$33$

Vedclass · Answer

(A) The system of equations can be written in matrix form $AX=B$ as: $\left[\begin{array}{ccc}1 & 2 & -1 \ 3 & -1 & 2 \ 2 & -2 & 3\end{array}ight]\left[\begin{array}{l}x \ y \ z\end{array}ight]=\left[\begin{array}{l}3 \ 1 \ 2\end{array}ight]$The augmented matrix is: $\left[\begin{array}{ccccc}1 & 2 & -1 & : & 3 \ 3 & -1 & 2 & : & 1 \ 2 & -2 & 3 & : & 2\end{array}ight]$Applying row operations $R_2 ightarrow R_2-3R_1$ and $R_3 ightarrow R_3-2R_1$:$\sim\left[\begin{array}{ccccc}1 & 2 & -1 & : & 3 \ 0 & -7 & 5 & : & -8 \ 0 & -6 & 5 & : & -4\end{array}ight]$Applying $R_3 ightarrow 7R_3-6R_2$:$\sim\left[\begin{array}{ccccc}1 & 2 & -1 & : & 3 \ 0 & -7 & 5 & : & -8 \ 0 & 0 & 5 & : & 20\end{array}ight]$Since $\operatorname{Rank}(A:B)=\operatorname{Rank}(A)=3$,the system has a unique solution.From the row-echelon form:$5z=20 \Rightarrow z=4$$-7y+5(4)=-8 \Rightarrow -7y=-28 \Rightarrow y=4$$x+2(4)-4=3 \Rightarrow x+4=3 \Rightarrow x=-1$Wait,re-calculating: $x+8-4=3 \Rightarrow x+4=3 \Rightarrow x=-1$. Let's re-check the system: $x+2y-z=3 \Rightarrow -1+8-4 = 3$ (Correct).So,$\alpha=-1, \beta=4, \gamma=4$.Then $\alpha^2+\beta^2+\gamma^2 = (-1)^2 + 4^2 + 4^2 = 1 + 16 + 16 = 33$.

If the solution for the system of equations $x+2y-z=3$,$3x-y+2z=1$ and $2x-2y+3z=2$ is $(\alpha, \beta, \gamma)$,then $\alpha^2+\beta^2+\gamma^2=$

Similar Questions

The following system of linear equations is given: $2x + 3y + 2z = 9$,$3x + 2y + 2z = 9$,and $x - y + 4z = 8$. Which of the following statements is true?

If a system of three linear equations in three unknowns,which is in the matrix equation form of $AX = D$,is inconsistent,then $\frac{\text{rank of } A}{\text{rank of } AD}$ is

If the system of linear equations
$7x + 11y + \alpha z = 13$
$5x + 4y + 7z = \beta$
$175x + 194y + 57z = 361$
has infinitely many solutions,then $\alpha + \beta + 2$ is equal to

The values of $\lambda$ and $\mu$ for which the system of linear equations $x+y+z=2$,$x+2y+3z=5$,and $x+3y+\lambda z=\mu$ has infinitely many solutions are,respectively:

Consider the following system of equations in matrix form $\begin{bmatrix} 1 \\ 2 \\ \lambda \end{bmatrix} \begin{bmatrix} 1 & 2 & \lambda \end{bmatrix} \begin{bmatrix} x \\ y \\ z \end{bmatrix} = 0$. Then which one of the following statements is true?

Vedclass Test Series

Exam Paper Generator

Online Exam Module