MathematicsHard244×since 2002Q4658If P = \left[ {\matrix{
{{{\sqrt 3 } \over 2}} & {{1 \over 2}} \cr
{ - {1 \over 2}} & {{{\sqrt 3 } \over 2}} \cr
} } \right],A = \left[ {\matrix{
1 & 1 \cr
0 & 1 \cr
} } \right]\,\,\,
Q = PAP^T, then P^T Q²⁰¹⁵ P is :