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Let vec(a)=hat(i)+2hat(j) and vec(b)=2ha...

Let `vec(a)=hat(i)+2hat(j)` and `vec(b)=2hat(i)+hat(j)`.
(i) Then, `|vec(a)|=|vec(b)|`
(ii) Then vectors `vec(a)` and `vec(b)` are equal.

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The correct Answer is:
To solve the question, we need to analyze the two statements about the vectors \(\vec{a}\) and \(\vec{b}\). Given: \[ \vec{a} = \hat{i} + 2\hat{j} \] \[ \vec{b} = 2\hat{i} + \hat{j} \] ### Step 1: Find the magnitudes of \(\vec{a}\) and \(\vec{b}\) The magnitude of a vector \(\vec{v} = x\hat{i} + y\hat{j} + z\hat{k}\) is given by the formula: \[ |\vec{v}| = \sqrt{x^2 + y^2 + z^2} \] #### For \(\vec{a}\): \[ |\vec{a}| = \sqrt{(1)^2 + (2)^2} = \sqrt{1 + 4} = \sqrt{5} \] #### For \(\vec{b}\): \[ |\vec{b}| = \sqrt{(2)^2 + (1)^2} = \sqrt{4 + 1} = \sqrt{5} \] ### Conclusion for Statement (i): Since \( |\vec{a}| = \sqrt{5} \) and \( |\vec{b}| = \sqrt{5} \), we can conclude that: \[ |\vec{a}| = |\vec{b}| \] Thus, Statement (i) is **TRUE**. ### Step 2: Check if the vectors \(\vec{a}\) and \(\vec{b}\) are equal Two vectors are equal if their corresponding components are equal. #### Components of \(\vec{a}\): - \(x\) component: \(1\) - \(y\) component: \(2\) #### Components of \(\vec{b}\): - \(x\) component: \(2\) - \(y\) component: \(1\) Since the \(x\) component of \(\vec{a}\) (which is \(1\)) is not equal to the \(x\) component of \(\vec{b}\) (which is \(2\)), and the \(y\) component of \(\vec{a}\) (which is \(2\)) is not equal to the \(y\) component of \(\vec{b}\) (which is \(1\)), we conclude that: \[ \vec{a} \neq \vec{b} \] Thus, Statement (ii) is **FALSE**. ### Final Answer: (i) TRUE (ii) FALSE
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