Proof verification (exterior algebra and determinant)

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Let $f: V \to V$ a linear map and $\dim V = n$. We have that $f^{\ast}: \Lambda^n(V) \to \Lambda^n(V)$ is necessarily a multiplication by some constant $c$. Prove that $c = \det f$.

My attempt. $\quad$ First, $\dim \Lambda^n(V) = 1$. Since $f^{\ast}$ is linear, then $f^{\ast}$ must be a multiplication by a constant.

If $\{e_1,...,e_n\}$ is a basis of $V$, then

$$f^{\ast}(\omega(v_1,...,v_n)) = \omega(f(v_1),...,f(v_n)).\tag{1}$$

Also,

$$\omega(v_1,...,v_n) = \det(a_{ij})\omega(e_1,...,e_n)\tag{2}$$

if $$v_i = \sum_j a_{ij}e_j.$$ So, $$f(v_i) = \sum_j a_{ij}f(e_j).$$ Thus, $$f^{\ast}\omega = \det(a_{ij})\omega(f(e_1),...,f(e_n)) = (\det f)\omega$$


Is this correct?