Question

Номер 423, д-з..............................................

Answer 1

решения данных примеров:

Answer 2

$( alpha - beta )( alpha + beta )= alpha ^2- beta ^2 \ ( alpha pm beta )^2= alpha ^2pm2 alpha beta + beta ^2$

$(x+ sqrt{y} )(x -sqrt{y} )=x^2-y \ (sqrt{a} - sqrt{b} )(sqrt{a} + sqrt{b} )=a-b \ ( sqrt{11} -3)( sqrt{11} +3)=11-9=2 \ ( sqrt{10} + sqrt{7} )( sqrt{7}- sqrt{10} )=7-10=-3 \ ( sqrt{a} + sqrt{b} )^2=a+2 sqrt{ab} +b \ ( sqrt{m} - sqrt{n} )^2=m-2 sqrt{mn} +n \ ( sqrt{2} +3)^2=2+6 sqrt{2} +9=11+6 sqrt{2} \ ( sqrt{5} - sqrt{2} )^2=5-2 sqrt{10} +2=7-2 sqrt{10}$