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AP EAMCET202120 Aug 2021Evening ShiftMathematicsVector AlgebraActual

Let u → and v → be two non-zero vectors with the intermediate angle 45 ° . Then | u → × v → | =

Options

  1. A| u → | | v → |
  2. B2 | u → | | v → |
  3. Cu → · v →
  4. D| u → | + | v → |

Correct answer

C. u → · v →

Step-by-step solution

Given that, θ = 45 ο As we know that | u → × v → | = u → v → sin θ   &   u → · v → = u → v → cos θ | u → × v → | = u → v → sin 45 ο ⇒ | u → × v → | = u → v → 2 ⇒ | u → × v → | = u → v → cos 45 ο ⇒ | u → × v → | = u → · v →

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