Question
Write the value $\big(\hat{\text{i}}\times\hat{\text{j}}\big).\hat{\text{k}}+\hat{\text{i}}.\hat{\text{j}}$

Answer

$\big(\hat{\text{i}}\times\hat{\text{j}}\big).\hat{\text{k}}+\hat{\text{i}}.\hat{\text{j}}$$=\hat{\text{k}}.\hat{\text{k}}+0$
$=|\hat{\text{k}}|^2+0$
$=1^2+0$ $\big(\because|\text{k}|=1\big)$
$=1$

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