- #1

salman213

- 302

- 1

**1. Find the SMALLEST angle between the vectors T and S**

Given vectors T = 2ax — 6ay + 3az and S =ax + 2ay + az,

Given vectors T = 2ax — 6ay + 3az and S =ax + 2ay + az,

See the thing I am confused about is whether to use Cross Product or Dot Product. I used the dot product formula

TdotS = |T||S|cos

and solved for cos theta ((theta = cos-1))

I got 114 degrees

The solution I have uses CROSS PRODUCT and finds an angle 65 Degrees

I don't get why the cross product would give a smaller angle? Can anyone tell me

If i take 114 - 180 i get -66 but I don't get why I would subtract 180 *and also its a negative angle then..HELP!

See the thing I am confused about is whether to use Cross Product or Dot Product. I used the dot product formula

TdotS = |T||S|cos

and solved for cos theta ((theta = cos-1))

I got 114 degrees

The solution I have uses CROSS PRODUCT and finds an angle 65 Degrees

I don't get why the cross product would give a smaller angle? Can anyone tell me

If i take 114 - 180 i get -66 but I don't get why I would subtract 180 *and also its a negative angle then..HELP!

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