a, \(f\left(2\right)=2^3-4.2^2-7.2-1=8-16-14-1=-23\)

\(g\left(\dfrac{1}{2}\right)=\left(\dfrac{1}{2}\right)^4+\left(\dfrac{1}{2}\right)^3-\left(\dfrac{1}{2}\right)^2-7.\dfrac{1}{2}+2=\dfrac{1}{16}+\dfrac{1}{8}-\dfrac{1}{4}-\dfrac{7}{2}+2=-\dfrac{25}{16}\)

b,

\(f\left(x\right)-g\left(x\right)=x^3-4x^2-7x-1-\left(x^4+x^3-x^2-7x+2\right)\)

\(=x^3-4x^2-7x-1-x^4-x^3+x^2+7x-2\)

\(=-x^4-3x^2-3\)

a, f(2)=23−4.22−7.2−1=8−16−14−1=−23

g(12)=(12)4+(12)3−(12)2−7.12+2=116+18−14−72+2=−2516

b,

f(x)−g(x)=x3−4x2−7x−1−(x4+x3−x2−7x+2)

=x3−4x2−7x−1−x4−x3+x2+7x−2

=−x4−3x2−3