The unit vector in the direction of $3\hat{i} + 4\hat{j}$ is:
A$3\hat{i}+4\hat{j}$
B$\dfrac{3\hat{i}+4\hat{j}}{5}$
C$\dfrac{3\hat{i}+4\hat{j}}{25}$
D$\dfrac{3\hat{i}+4\hat{j}}{7}$
Answer & Solution
Correct answer: B. $\dfrac{3\hat{i}+4\hat{j}}{5}$
Unit vector = vector/|vector| = (3î+4ĵ)/√(9+16) = (3î+4ĵ)/5.
Related questions
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