Assertion $A$ : If $A, B, C, D$ are four points on a semi-circular arc with centre at $'O'$ such that $|\overrightarrow{{AB}}|=|\overrightarrow{{BC}}|=|\overrightarrow{{CD}}|$, then $\overrightarrow{{AB}}+\overrightarrow{{AC}}+\overrightarrow{{AD}}=4 \overrightarrow{{AO}}+\overrightarrow{{OB}}+\overrightarrow{{OC}}$

Reason $R$ : Polygon law of vector addition yields $\overrightarrow{A B}+\overrightarrow{B C}+\overrightarrow{C D}+\overrightarrow{A D}=2 \overrightarrow{A O}$

In the light of the above statements, choose the most appropriate answer from the options given below

981-1267

  • [JEE MAIN 2021]
  • A

    Both $A$ and $R$ are correct and $R$ is the correct explanation of $A$.

  • B

    $A$ is not correct but $R$ is correct.

  • C

    Both $A$ and $R$ are correct but $R$ is not the correct explanation of $A$.

  • D

    $A$ is correct but $R$ is not correct.

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