logo

Ask Questions, Get Answers

 
X
 Search
Want to ask us a question? Click here
Browse Questions
Ad
Home  >>  EAMCET  >>  Mathematics
0 votes

$\large\frac{x^2+x+1}{(x-1)(x-2)(x-3)}=\frac{A}{x-1}+\frac{B}{x-2}+\frac{C}{x-3}$ then find $A+C=$

\[\begin {array} {1 1} (a)\;4 & \quad (b)\;5 \\ (c)\;6 & \quad (d)\;8 \end {array}\]

Can you answer this question?
 
 

1 Answer

0 votes
<div class="clay6-step-odd"><div class="clay6-basic" id="pr10">Expand the equation and write it in matrix form. You will end up with -</div><div class="clay6-basic" id="pr11">$\begin{bmatrix} A \\ B \\ C \end{bmatrix} = {\begin{bmatrix} 1 &amp; 1 &amp; 1 \\ -5 &amp; -4 &amp; -3 \\ 6 &amp; 3 &amp; 2 \end{bmatrix} }^{\Large -1} \begin{bmatrix} 1 \\ 1 \\ 1 \end{bmatrix}$</div><div class="clay6-basic" id="pr12">The right hand side when solved will end up with</div><div class="clay6-basic" id="pr13">$A = \frac{3}{2}   \; B = 3  \; C = \frac{13}{2} $</div><div class="clay6-basic" id="pr14">So $ A + C = 8 $. Hence (d) is the right answer.</div></div>
answered Nov 7, 2013 by pady_1
edited Feb 3, 2014 by pady_1
 
Ask Question
student study plans
x
JEE MAIN, CBSE, NEET Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App
...