1)
2)
f(x+1)=12x+12-5= 12x + 7
f(x^2)= 12x^2-5
f(-x)=-12x-5
f(x^2-3) = 12x^2-36-5=12x^2-41
(x^3-3x^2)-(3x-9)=0
а)1,2*(5-а) = 6-1,2а