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**pavino14****Member**- Registered: 2017-07-09
- Posts: 3

If x=ai+bj , y=bj+ck , z=ai +ck, for which of the following triads (a,b,c) is x perpendicular to(z-y)?

1) (4 ,1 ,1)

2) (2 ,2 ,2)

3) (1 ,-1 ,1)

4) (-1, -2, 0

5) (1 ,2 ,0)

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First, compute . We see that:

Recall that two vectors are perpendicular if their dot product (also called scalar product) is zero.

So you want to show that the dot product of with is zero, for some choice of . Now all you have to do is try the different possibilities given and see which one gives you when you take the dot product.Feel free to let us know if you need more help!

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