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# Vectors watch

1. Given vector V=2i+3j-6k,find
a) the magnitude of V
b)the unit vector in direction of V
c) the vector in the direction opposite to V and with magnitude 10.5
d)the anglews which V make with the coordinate axis
Cannot do part c) and d)

2. Octavius the spider spins two successive threads along vectors a=i-3j+2k and b=4i+j-3k.Find
a)the angle through which Octavius turns at the junction of the two threads
b) the vector he must travel to form a triangular web
c)the angle this third side makes with the x-axis
Help in all parts
4.Vector V makes angle 50 degrees and 70 degrees with the positive x and y directions. Find two possible valvues of V if V magnitude=6.
Answers: 1c=-3i+4.5j+9k 1d=73.4, 64.4, 149
2a=105 2b=-5i+2j+k 2c=156
4)46.7 or 133.3
THANK YOU
2. (Original post by Asazycat)
Given vector V=2i+3j-6k,find
a) the magnitude of V
b)the unit vector in direction of V
c) the vector in the direction opposite to V and with magnitude 10.5
d)the anglews which V make with the coordinate axis
Cannot do part c) and d)

2. Octavius the spider spins two successive threads along vectors a=i-3j+2k and b=4i+j-3k.Find
a)the angle through which Octavius turns at the junction of the two threads
b) the vector he must travel to form a triangular web
c)the angle this third side makes with the x-axis
Help in all parts
4.Vector V makes angle 50 degrees and 70 degrees with the positive x and y directions. Find two possible valvues of V if V magnitude=6.
Answers: 1c=-3i+4.5j+9k 1d=73.4, 64.4, 149
2a=105 2b=-5i+2j+k 2c=156
4)46.7 or 133.3
THANK YOU
1c) Take the unit vector you find in part b. If you multiply it by -1, then the vector will go in the opposite direction. If you multiply by some scalar number, that number will be the magnitude of the vector.

1d) Take . Then quite simply the angles the vector makes between the , , and axis is then obviously you can get your angle

2a) So find the angle between the two vectors. ring any bells?

2b) Say the triangle is ABC with A being the position vector and likewise for B. Then if he travels along A, then along B, what vector must be go along to get back to A?

2c) Same principle as 1c

4) I dont understand the question... please elaborate?

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