1 supra 4 plus 2 supra 3 ori paranteza rotunda 8 supra 9 parateza rotunda la puterea minus 1


Răspuns :

1/4+2/3×(8/9)⁻¹=
=1/4+2/3×1/(8/9)=
=1/4+2/3×9/8=
=1/4+3/4=
=4/4=1