The value of non-zero scalars α and β for all vectors <span class="math-tex">\(\vec a\)</span> and <span class="math-tex">\(\vec b\)</span>, such that <span class="math-tex">\(\rm \alpha\left(2\vec a-\vec b \right)+\beta\left(\vec a + 2\vec b\right)=8\vec b - \vec a \)</span> is:
Compare the coefficients of \(\vec{a}\) and \(\vec{b}\) (they can be any vectors):
From the first, \(\beta = -1 - 2\alpha\). Substitute: \(-\alpha - 2 - 4\alpha = 8 \Rightarrow \alpha = -2\), then \(\beta = 3\).
Answer: (D) α = −2, β = 3
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