①535^2x4-465^2x4
=4×(535²-465²)
=4×(535+465)(535-465)
=4×1000×70
=280000
②202^2+202x196+98^2
=202²+2×202×98+98²
=(202+98)²
=300²
=90000
①535^2x4-465^2x4
=4×(535²-465²)
=4×(535+465)(535-465)
=4×1000×70
=280000
②202^2+202x196+98^2
=202²+2×202×98+98²
=(202+98)²
=300²
=90000