how to find matrics B....plz help me
Answers
Explanation:
let B = b1 b2
b3 b4
Now,
2 5 b1 b2 17 -1
=
-3 7 b3 b4 47 13
[row x column]
2 x b1 + 5 x b3 = 17 ...... (i)
2 x b2 + 5 x b4 = -1 ...... (ii) [please recheck whether the RHS is 1 or -1]
similarly,
-3 x b1 + 7 x b3 = 47 ..... (iii)
-3 x b2 + 7 x b4 = 13 ...... (iv)
take (i) & (ii)
[either use substitution or elimination method which we have learned in lower classes. Here let us use elimination]
To eliminate b1 , multiply eq. (i) by 3 && eq. (ii) by 2
(i)========== 6 b1 + 15 b3 = 51
(ii)========= -6 b1 + 14 b3 = 94
add these 2 ens.
29 b3 == 145
b3 == 5
sub this value in (i) or (ii)
(i)=== 2 b1 + 5 b3 = 17
2 b1 + 5*5 = 17
2 b1 = 17 - 25 = -8
b1 = -4
similarly take (ii) & (iv) , multiply (ii) by 3 && (iv) by 2
COULD U PLS CHECK the RHS.. FIRST ROW second term has to be '1' , i guess. i am doing it with '1' from here on..
6 b2 + 15 b4 = 3
-6 b2 + 14 b4 = 26
adding both :
29 b4 = 29
b4 = 1
(ii)=== 2 b2 + 5 b4 = 1
2 b2 =1 -5 = -4
b2 = -2
B = -4 -2
5 1
Make equations and solve
Eg:- 2B =17
B= 17/2
5B= -1
B= -1/5
-3B= 47
B= -47/3
7B= 13
B=13/7
The resulting matrix B will me:-
[ 17/2 -1/5
-47/3 13/7 ]