Question
If P & Q are two vectors such that |P-Q| = |P+Q| , then find angle between P and Q.
Read 3 Solution.
I P-QI2= IP+QI2
P2 + Q2 -2PQCOSθ = P2+Q2+2PQCOSθ
-4PQCOSθ=0
θ=900
Best SolutionSARIKA SHARMA 11 year ago
is this solution helpfull: 2 0
IP-QI2=IP+QI2
P2+Q2-2PQcosθ=p2 +Q2+2PQCOSθ
ON SOLVING WE VYL GETθ=900
SARIKA SHARMA 11 year ago
is this solution helpfull: 2 0
θ=90
|P-Q|=|P+Q|
OR, -2PQCOSθ=2PQCOSθ
OR, 4PQCOSθ=0
BUT P AND Q≠0
SO
COSθ=0=COS90
Therefore, θ=90
PRINCE PAL 11 year ago
is this solution helpfull: 1 0