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The only way to get a negative dot product is to have an angle larger than 90 degrees.

The formula is ABcos(theta)

False because from 3pi/2 to 2pi the cos is positive and 3pi/2 and 2pi is larger than 90 degrees.

Right?

Stephen

- Thread starter StephenDoty
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- #1

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The only way to get a negative dot product is to have an angle larger than 90 degrees.

The formula is ABcos(theta)

False because from 3pi/2 to 2pi the cos is positive and 3pi/2 and 2pi is larger than 90 degrees.

Right?

Stephen

- #2

nrqed

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The only way to get a negative dot product is to have an angle larger than 90 degrees.

The formula is ABcos(theta)

False because from 3pi/2 to 2pi the cos is positive and 3pi/2 and 2pi is larger than 90 degrees.

Right?

Stephen

- #3

CompuChip

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<off-topic>

If you insist: False, just take a non-Euclidean metric.

</off-topic>

If you insist: False, just take a non-Euclidean metric.

</off-topic>

- #4

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so is it true or false

and why????

thank you

and why????

thank you

- #5

nrqed

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I meant to say that most people would say that it's true that "The only way to get a negative dot product is to have an angle larger than 90 degrees"so is it true or false

and why????

thank you

- #6

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2. because from 3pi/2 to 2pi the cos is positive and 3pi/2 and 2pi is larger than 90 degrees.

The second statement is NOT in contradiction with the first. The first statement does not say that ALL angles larger than 90 degrees give a negative dot product

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