i)f(x)=4x-1,so 4x-1>=3-2x,4x-1>=2x-3,x>=2/3,minf(x)=f(2/3)=5/3
ii)f(x)=3-2x,so 3-2x>=4x-1,3-2x>=2x-3,x=4x-1,2x-3>=3-2x,x extinct
so,minf(x)=5/3