∣P∣=∣Q∣=x…(i)
∣P+Q∣=n∣P−Q∣
P2+Q2+2PQcosθ=n2(P2+Q2−2PQcosθ)
Using(i) in above equation,
cosθ=1+n2n2−1
θ=cos−1(n2+1n2−1)
Two vectors P and Q have equal magnitudes. If the magnitude of P+Q is n times the magnitude of P−Q, then angle between P and Q is
Held on 20 Jul 2021 · Verified 6 Jul 2026.
sin−1(n+1n−1)
cos−1(n+1n−1)
sin−1(n2+1n2−1)
cos−1(n2+1n2−1)
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