1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Vlada [557]
2 years ago
9

PLEASE HELP! find the inverse matrix​

Mathematics
2 answers:
nikitadnepr [17]2 years ago
5 0

Answer:

Step-by-step explanation:

A=\begin{bmatrix}11&-5\\3&-1\end{bmatrix}\\det(A)=11*(-1)-3*(-5)=-11+15=4\\minor=\begin{bmatrix}-1&3\\-5&11\end{bmatrix}\\cofactor=\begin{bmatrix}-1&-3\\5&11\end{bmatrix}\\Transposed\ cofactor=\begin{bmatrix}-1&5\\-3&11\end{bmatrix}\\A^{-1}=\dfrac{Transposed\ cofactorx}{det(A)} =\begin{bmatrix}\dfrac{-1}{4} &\dfrac{5}{4} \\\\ \dfrac{-3}{4} &\dfrac{11}{4}\end{bmatrix}\\

Proof:\\A*A^{-1}=\begin{bmatrix}11&-5\\\\3&-1\end{bmatrix}*\begin{bmatrix}\dfrac{-1}{4} &\dfrac{5}{4}\\\\ \dfrac{-3}{4}&\dfrac{11}{4}\end{bmatrix}\\\\\\=\begin{bmatrix}\dfrac{-11+15}{4} &\dfrac{55-55}{4}\\\\ \dfrac{-3+3}{4}&\dfrac{15-11}{4}\end{bmatrix}\\\\\\=\begin{bmatrix}1&0\\\\ 0&1\end{bmatrix}\\

Bonus: method of Gauss 's pivot jointed

Download xls
Sauron [17]2 years ago
3 0

Answer:

see explanation

Step-by-step explanation:

The inverse of a matrix A = \left[\begin{array}{ccc}a&b\\c&d\\\end{array}\right] is

A^{-1} = \frac{1}{ad-bc} \left[\begin{array}{ccc}d&-b\\-c&a\\\end{array}\right]

If ad - bc = 0 then the matrix has no inverse

A = \left[\begin{array}{ccc}11&-5\\3&-1\\\end{array}\right]

ad - bc = (11 × - 1) - (- 5 × 3) = - 11 - (- 15) = - 11 + 15 = 4 , then

A^{-1} = \frac{1}{4} \left[\begin{array}{ccc}-1&3\\-5&11\\\end{array}\right] = \left[\begin{array}{ccc}-0.25&0.75\\-1.25&2.75\\\end{array}\right]

You might be interested in
Solve algebraically 10+f=10
Sunny_sXe [5.5K]
10 + f = 10
-10         -10


f = 10 - 10

f = 0.
4 0
2 years ago
Which of the following angle pairs<br> are<br> NOT congruent?
Slav-nsk [51]

Answer:

<2 and <8

Step-by-step explanation:

8 0
2 years ago
Kimmi and her mom count 254 guests coming to the wedding. There are 9 tables at the wedding. How many guests sit at each table?
valkas [14]

Answer:

28 guests with 2 guests remaining

Step-by-step explanation:

254/9 = 28.2222222

so 28 remainder 2

hope this helps :) mark brainliest?

6 0
2 years ago
Solve each inequality graphically.<br><br>|x-3|-2&gt;-1​
Nutka1998 [239]

Answer:

•this is axample

•what the number

•|x-3|-2>-1

Step-by-step explanation:

<h2>#CarryOnLearning</h2>
4 0
3 years ago
What is the factored form of y^2+6y-16
Vlada [557]
<h2><em>y 2 + 6 y − 16 = ( y + 8 ) ( y − 2 )   </em></h2><h2 /><h2><em>Explanation: </em></h2><h2><em>Note that in general: </em></h2><h2 /><h2><em>( y + a ) (y − b ) = y 2 + ( a − b ) y − a b </em></h2><h2 /><h2><em>So we want to find a pair of factors  a  and  b  of  16  which differ by  6 .  </em></h2><h2><em>The pair  8 , 2 works in that  8− 2 = 6  and  8 ⋅ 2= 16 . </em></h2><h2 /><h2><em>Hence: </em></h2><h2><em> y 2 + 6 y − 16 = ( y+ 8 ) ( y − 2 )</em></h2><h2><em>y=2,-8</em></h2>
6 0
3 years ago
Read 2 more answers
Other questions:
  • Identify the zeros of f(x) = (x + 9)(x − 4)(6x + 1).
    6·2 answers
  • If lisa has 2,134 buttons that needed to be sorted equally into 12 jars.How many buttons will be in each jar.
    8·1 answer
  • What is 1/6+7/10 as a equivalent fraction
    9·1 answer
  • I need help with my homework
    9·1 answer
  • Please help with letter b.
    10·1 answer
  • A number cube with the numbers 1 through 6 is rolled. Find the given probability
    6·2 answers
  • Use the parabola tool to graph the quadratic function f(x)=−x2+4. Graph the parabola by first plotting its vertex and then plott
    7·1 answer
  • How many pairs are parelof
    11·2 answers
  • A marble is randomly selected from a bag containing 3 red marbles, 3 blue marbles and 3 green marbles. What is the probability t
    11·2 answers
  • A Delivery service charges $25 per pound for making a delivery. If there is an additional 8% sales tax, what is the cost of deli
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!