Решите неравенство f'(x)<0<br> 1) f(x)= 3/x-x^2 2) f(x)=x^4-4,5x^2+2 3) f(x)=-1/x^2-1/x-5 4)f(x)=x^4-4x-3
1) f'(x)=(3/x - x^2)'=-3/x^2-2x; 2)f'(x)=(x^4-4,5x^2+2)'=4x^3-9x; 3)f'(x)=(-1/x^2-1/x-5)'=2x/x^4+1/x^2=2/x^3+1/x^2; 4)f'(x)=4x^3-4.