15. {[23-(48:6×2-4+2):2]:2+4}:3-3=
={[23-(16-4+2):2]:2+4}:3-3=
=[(23-14:2):2+4]:3-3=
=[(23-7):2+4]:3-3=
=(16:2+4):3-3=
=(8+4):3-3=
=12:3-3=
=4-3=
=1
16. 3×{3+3×[3+3×(3+3)]+3-3²}=
=3×[3+3×(3+3×6)+3-3²]=
=3×[3+3×(3+18)+3-3²]=
=3×(3+3×21+3-3²)=
=3×(3+3×21+3-9)=
=3×(3+36+3-9)=
=3×33=
=99
17. [5×(12-2×5):2]²=
=[5×(12-10):2]²=
=(5×2:2)²=
=5²=
=25 daca se poate, imi poti da coronita pls???
