А)...=53/12+11/24-4/24=(106+11-4)/24=113/24
б)...=12/15+34/15-18/15=(12+34-18)/15=28/15
а)...=-(11/40*26/33*35/39)=-7/36
б)...=-(28/13*33/34*17/101)=-33/98
3x²-7x+2
2-6x
10x+2
2-6x = 5x²
3
5x²=3
x²=3:5=0.6
x²=0.6•2=1.2
1+2x>0⇒x>-0,5
log(0,7)(1+2x)>2⇒1+2x<0,49⇒2x<-0,51⇒x<-0,255
x∈(-0,5;-0,255)