Răspuns:
Nu le stiu pe toate,te ajut la ce pot
26.
/=supra
(5!/4!(5-4)!)+1=3!
(5!/4!×1!)+1=3!
(4!×5/4!+1)+1=3!
(5/1)+1=6
5+1=6
6=6
27.
(5!/1!(5-1)!)+(5!/3!(5-3)!)+(5!/5!(5-5)!)=16
(5!/1!×4!)+(5!/3!×2!)+(5!/5!×1!)=16
(4!×5/1×4!)+(3!×4×5/3!×2)+(5!/5!×1)=16
5+10+1=16
16=16
29.
Combinări de 5 luate câte 2,ceva de genul C⅖= 5!/2!×3!=3!×4×5/2×3!=20/2=10
30.
C¼=4!/1!×3!=3!×4/1×3!=4/1=4
31.
C¾=4!/3!×1!=3!×4/3!×1=4/1=4
