62,8²-62,7²=(62,8-62,7)*(62,8+62,7)=0,1*125,5=12,55.
(d¹⁰+m¹⁰)²-(d¹⁰-m¹⁰)²-d²m²=
d²⁰+2d¹⁰m¹⁰+m²⁰-d²⁰+2d¹⁰m¹⁰-m²⁰-d²m²=
4d¹⁰m¹⁰-d²m²=d²m²*(4d⁸m⁸-1)=
=d²m²*(2d⁴m⁴-1)*(2d⁴m⁴+1)=
=d²m²*(√2d²m²-1)*(√2*d²m²+1)*(2d⁴m⁴+1)=
=d²m²*(⁴√2*dm-1)*(⁴√2*dm+1)*(√2*d²m²+1)*(2d⁴m⁴+1).