Elsatntask
a fost răspuns

2 supra 3x5+2 supra 5×7+2 supra 7×9+............+2 supra 31×33 urgenttttt!dau coroana​

Răspuns :

Răspuns:

Explicație pas cu pas:

2/3x5+2/5x7+2/7x9+......+2/31x33

1/3x5=1/2x3-1/2x52(1/3x5+1/5x7+.................+1/31x33)=

       2(1/2x3-1/2x5+1/2x5-1/2x7+................+1/2x29-1/2x31+1/2x31-1/2x33)=

      =2×1/2×(33-3)/3x33=30/3x33=10/33

Ask Alte intrebari