Let A=[ x2 6 9 3 y2 9 4 5 z2 ],B=[ 2x 3 5 2 2y 6 1 4 2z-3 ] if traceA=traceB, then x+y+z is equal to

Question

Let A=[ x2 6 9 3 y2 9 4 5 z2 ],B=[ 2x 3 5 2 2y 6 1 4 2z-3 ] if traceA=traceB, then x+y+z is equal to (A) 1 (B) 2 (C) 3 (D) None of those

Tardigrade Admin · Accepted Answer

Trace A=x2+y2+z2 Trace B=2x+2y+2z-3 x2+y2+z2=2x+2y+2z-3 x2+y2+z2-2x-2y-2z+3=0 (x - 1)2+(y - 1)2+(z - 1)2=0 It is true if x=1,y=1,z=1 So, x+y+z=3

Q. Let $A = ⎣ ⎡ x^{2} 34 6 y^{2} 5 99 z^{2} ⎦ ⎤, B = ⎣ ⎡ 2 x 21 3 2 y 4 56 2 z - 3 ⎦ ⎤$ if $t r a ce A = t r a ce B,$ then $x + y + z$ is equal to