F(x)=3cosx-7x²
f'(x)=-3sinx-14x f'(0)=0 буква Т
f(x)=4x-x²
f'(x)=4-2x f'(0)=4-2·0=4 буква Е
f(x)=2√x+1/x³
f'(x)=1/√x-3/x⁴ f'(1)=1-3=-2 буква Л
f(x)=(1-x)/(x+1)
f'(x)=(1-x)'(x+1)-(1-x)(x+1)'/(x+1)²=-(x+1)-(1-x)/(x+1)²=-2/(x+1)²
f'(2)=-2/3²=-2/9 буква О