Odpowiedzi

2009-12-13T18:58:30+01:00
2009-12-13T19:21:43+01:00
= [4√5 -6√2]/[4√5 +6√2] - [4√5 +6√2]/[4√5 - 6√2] =
= [4√5 - 6√2]²/[80 -72] - [4√5 +6√2]²/[80 - 72] =
= [ 80 - 48√10 + 72] / 8 - [80 +48√10 +72] /8 =
= [ 80 -48√10 + 72 - 80 -48√10 - 72]/ 8 =[ - 96√10] / 8 = -12√10
bo
√80 = √(16*5) =√16 *√2 = 4√5
√72 = √(36*2) = √36 * √2 = 6√2