Given |vector a| = 3, |vector b| = 5, and |vector a + vector b| = 7, determine |vector a - vector b|.
answer: 4.26
Can somebody please explain how you solve this question? It's too hard for me...
answer: 4.26
Can somebody please explain how you solve this question? It's too hard for me...
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When in doubt.........sketch it out...........
Draw horizontal line AB 3 units long....from B swing an arc of radius 5 units.......from A swing an arc of 7 units radius to intersect the arc from B, at C.......you now have graphical representation of the given vectors.
Now. extend the line CB backwards by -5 units from B, ending at D......line DA is [vector a - vector b]
Calculate (or measure) magnitude of [vector a - vector b].
Draw horizontal line AB 3 units long....from B swing an arc of radius 5 units.......from A swing an arc of 7 units radius to intersect the arc from B, at C.......you now have graphical representation of the given vectors.
Now. extend the line CB backwards by -5 units from B, ending at D......line DA is [vector a - vector b]
Calculate (or measure) magnitude of [vector a - vector b].