Question

Вычислить:
а) 101^2 - 202 * 81 + 81^2
б) 53^2 - 32^2
___________
62^ 2 - 44^2
плииииз

Answer 1

$\displaystyle\bf\\1)\\\\101^{2} -202\cdot81+81^{2} =101^{2} -2\cdot 101\cdot81+81^{2} =\\\\=(101-81)^{2} =20^{2} =400\\\\\\2)\\\\53^{2} -32^{2} =(53-32)(53+32)=21\cdot85=1785\\\\\\3)\\\\62^{2} -44^{2} =(62-44)(62+44)=18\cdot106=1908$