grandes-ecoles 2014 QV.B.4

grandes-ecoles · France · centrale-maths2__pc Number Theory Quadratic Diophantine Equations and Perfect Squares
Show that every natural integer is a sum of four squares of integers. 
Show that every natural integer is a sum of four squares of integers.
Paper Questions
QI.A.1 QI.A.2 QI.B.1 QI.C.1 QI.C.2 QI.C.3 QI.D.1 QI.D.2 QI.E.1 QI.E.2 QI.E.3 QII.A.1 QII.A.2 QII.A.3 QII.B.1 QII.B.2 QIII.A.1 QIII.A.2 QIII.B.1 QIII.B.2 QIII.B.3 QV.A QV.B.1 QV.B.2 QV.B.3 QV.B.4