Which one of the following is not true?

\(|\vec{a}|=|\vec{b}|\Rightarrow \vec{a}=\vec{b}\)

\(|\vec{a}\times \vec{b}|=(\vec{a})^2(\vec{b})^2-(\vec{a}\cdot \vec{b})^2\)

\(\vec{a}\times (\vec{b}\cdot \vec{c})\) is not defined

If the adjacent sides of a parallelogram are represented by the vectors \(\vec{a}\) and \(\vec{b}\) respectively, then its area is \(|\vec{a}\times \vec{b}|\)