From the above diagram, the equations are,
OA=R[cos30∘i^+sin30∘j^]
OB=R[cos60∘i^−sin60∘j^]
OC=R[−cos45∘i^+sin45∘j^]
⇒OA+OB−OC=R[21+23+21]i^+R[21−23−21]j^, angle with the x−axis.
⇒tanα=21+23+2121−23−21=1+3+21−3−2
⇒α=tan−1[1+3+21−3−2].
The magnitude of vectors OA, OB and OC in the given figure are equal. The direction of OA+ OB- OC with x-axis will be:
JEE Main 2021 — Physics Mechanics
2021mcqmedium
The magnitude of vectors OA,OB and OC in the given figure are equal. The direction of OA+OB−OC with x−axis will be:
Official previous-year question
Held on 26 Aug 2021 · Verified 1 Jul 2026.
Options
- A
tan−1(1+3−2)(3−1+2)
- B
tan−1(1+3+2)(1−3−2)
- C
tan−1(1−3+2)(3−1+2)
- D
tan−1(1−3−2)(1+3−2)
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