Given: ∣A+B∣=2∣A−B∣
We have,
A2+A2+2A2cosθ=4(A2+A2−2A2cosθ)
Simplifying we get
2A2+2A2cosθ=8A2−8A2cosθ
⇒1+cosθ=4−4cosθ
⇒5cosθ=3⇒cosθ=53⇒θ=cos−153
Two vectors A and B have equal magnitudes. If magnitude of A+B is equal to two times the magnitude of A−B, then the angle between A and B will be
Held on 29 Jun 2022 · Verified 1 Jul 2026.
cos−1(53)
cos−1(31)
sin−1(31)
sin−1(53)
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