9-4 =(3+2)(3-2) =5(√3+√2)(√3-√2) =(√75+√50)(√75-√50)/5 =[(√75)²-(√50)²]/5 =5²/5 =(3+2)²/5 =(3²+12+2²)/5 =(2²+4+1+12+2²)/5 =(2³+17)/5 =[2+(³√17)][4-2(³√17)+(³√17)²]/5 =[8-4(³√17)+2(³√17)²+4(³√17)-2(³√17)²+(³√17)³]/5 =(8+17)/5 =25/5 =5/1 =5