Maths-
General
Easy
Question
The system AX = B of n equations in n unknowns has infinitely many solutions if
- det A
0
- det A = 0, (adjA)B O
- det A = 0, (adjA)B = O
- det A 0, (adjA)B = O
0
O
0, (adjA)B = O
The correct answer is: det A = 0, (adjA)B = O
X = A–1B
X = 
Clearly if the system has infinite solutions
|A| = 0 and (adj A)B = O
Hence (c) is the correct answer.
Related Questions to study
Maths-
The value of 
is :
The value of is :
Maths-General
Maths-
is equal to
is equal to
Maths-General
Maths-
If z lies on the circle ½z½=1, then 
lies on
If z lies on the circle ½z½=1, then lies on
Maths-General
Maths-
If z = x + iy, and 
then ½w½ = 1 implies that in the complex plane
If z = x + iy, and then ½w½ = 1 implies that in the complex plane
Maths-General
Maths-
If 
=1 and arg (z1 z2) = 0, then
If =1 and arg (z1 z2) = 0, then
Maths-General
Physics-
A siren emitting sound of frequency 500 Hz is going away from a static listener with a speed of 50 m/sec The frequency of sound to be heard, directly from the siren
A siren emitting sound of frequency 500 Hz is going away from a static listener with a speed of 50 m/sec The frequency of sound to be heard, directly from the siren
Physics-General
Physics-
The Doppler’s effect is applicable for
The Doppler’s effect is applicable for
Physics-General
Physics-
Two vibrating tuning forks produce progressive waves given by yl = 4 sin 500 pt and Y2 = 2 sin 506pt Number of beats produced per minute is
Two vibrating tuning forks produce progressive waves given by yl = 4 sin 500 pt and Y2 = 2 sin 506pt Number of beats produced per minute is
Physics-General
Maths-
If A = {1, 2, 3}, B = {3, 4}, C = {4, 5, 6}, then 
is equal to
If A = {1, 2, 3}, B = {3, 4}, C = {4, 5, 6}, then is equal to
Maths-General
Maths-
x may have values:
x may have values:
Maths-General
Maths-
In a group of children, 35 play football out of which 20 play footballs only, 22 play hockey; 25 play cricket out of which 11 play cricket only. Out of these 7 play cricket and football but bot hockey, 3 play football and hockey but not cricket and 12 play football and cricket both.
How many plays hockey only ?
In a group of children, 35 play football out of which 20 play footballs only, 22 play hockey; 25 play cricket out of which 11 play cricket only. Out of these 7 play cricket and football but bot hockey, 3 play football and hockey but not cricket and 12 play football and cricket both.
How many plays hockey only ?
Maths-General
Chemistry-
In the evaporation of water, the entropy:
In the evaporation of water, the entropy:
Chemistry-General
Chemistry-
The enthalpy changes at 298 K in successive breaking of O-H bonds of water are
and
The bond enthalpy of O-H bond is:
The enthalpy changes at 298 K in successive breaking of O-H bonds of water are
and The bond enthalpy of O-H bond is:
Chemistry-General
Chemistry-
Energy required to dissociate 4 g of gaseous hydrogen into free gaseous atoms is 208 kcal at '250 C The bond energy of H-H bond will be:
Energy required to dissociate 4 g of gaseous hydrogen into free gaseous atoms is 208 kcal at '250 C The bond energy of H-H bond will be:
Chemistry-General
Maths-
A vector of magnitude 10 and perpendicular to 
and 
is
A vector of magnitude 10 and perpendicular to and is
Maths-General
