1) 2 1/2 + 1 3/4 = 2 2/4 + 1 3/4 = 3 5/4 = 4 1/4
2) 6 2/3 + 4 4/5 = 6 10/15 + 4 12/15 = 10 22/15 = 11 7/15
3) 4 * 4 1/4 = 4 * 17/4 = 17
4) 11 7/15 : 2 = 172/15 * 1/2 = 86/15 = 5 11/15
5) 17 - 5 11/15 = 16 15/15 - 5 11/15 = 11 4/15
<span>A) 7a²-28=7(a²-4)=7(а+2)(а-2)
б) -2b²+18=-2(b²-9)=-2(</span>b+3)(b-3)
F(x)=-1/3*cos3x-4tg(x/2)+C