1) =4[(x-1/2)'(5-3x)+(5-3x)'(x-1/2)]=4[5-3x-3(x-1/2)]=4[5-3x-3x+3/2]=20-24x+6=26-24x
2) (x+6)'(3-x)(7+x)+(x+6)((3-x)(7+x))'=(3-x)(7+x)+(x+6)[(3-x)'(7+x)+(3-x)(7+x)']=
=(3-x)(7+x)+(x+6)[-7-x+3-x]=(3-x)(7+x)+(x+6)(-4-2x)=21-x^2-4x-(x+6)(x+2)2=
=-x^2-4x+21-2x^2-24-16x=-(3x^2+20x+3)