Question

(9√5+7√2)(7√2-9√5)-(6√10-0,2√5 )^2

Answer 1

(9√5+7√2)(7√2-9√5)-(6√10-0,2√5 )^2 = (7√2+9√5)(7√2-9√5) - (6√10-0,2√5 )^2 = (98 - 405) - (360 - 12√2 + 2) = 98 - 405 - 362 + 12√2 = 12√2 - 669 = 4√2 - 223