Answer: a) k(x) = 2ˣ
Step-by-step explanation:
[tex]g(x) = 3(2^x)\qquad h(x)=2^{x+1}\\\\k(x) = (g-h)(x)\\.\qquad =3(2^x)-2^{x+1}\\.\qquad =3(2^x)-2^x\cdot 2^1\\.\qquad =3(2^x)-2(2^x)\\.\qquad =1(2^x)\\.\qquad =\large\boxed{2^x}[/tex]