If `O `be the origin and `P(2, 3, 4)` and `Q(1, -2,1) `be any two points, show that `OP OQ.`

O is the origin, P(2,3,4) and Q(1,k,1) are points such that bar(OP)botbar(OQ). Find k.

If O is the origin and P = (1, -2, 1) and OP bot OQ , then Q =

If O be the origin and if P(x_1, y_1) and P_2 (x_2, y_2) are two points, the OP_1 (OP_2) sin angle P_1OP_2 , is equal to

If O is the origin P(2,3) and Q(4,5) are two, points, then OP*OQ cos anglePOQ =

If O is the origin P(2,3) and Q(4,5) are two, points, then OP*OQ cos anglePOQ =

O is the origin , P(2,3,4), Q(1,k,1) are points such that bar(OP) _|_ bar(OQ) then find k.

If O is the origin and P=(2, 3), Q=(4, 5) then OP*OQ cos angle POQ=