Question

Two vectors both equal in magnitude have their resultant equal in magnitude of the Other find the angle between the two vectors

Answer 1

Hope u like my process
=====================
Formula to be used::
=-=-=-=-=-=-=-=-=-=-=-=
|R|² = |a|² +|b|² +2 |a||b| cos¢

Where R = resultant vector,

a & b are two vectors

and, ¢ is the angle between two vectors
_______________________________

Let the magnitude of any vector be x

So, R = a = b = x [since all are equal]

Now, by formula,

=> |R|² = |a|² +|b|² +2 |a||b| cos¢

or, x² = x² +x² +2.x.x.cos¢

or, x² - 2x² = 2x² cos¢

$or. \: \: - {x}^{2} = 2 {x}^{2} \cos( \theta ) \\ \\ or. \: \: \cos( \theta ) = \frac{ - {x}^{2} }{2 {x}^{2} } = - \frac{1}{2} \\ \\ or. \: \: \cos( \theta ) = \cos(120) = \cos( \frac{2\pi}{3} ) \\ \\ or. \: \: \theta = 120 = \frac{2\pi}{3}$
_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
Hope this is ur required answer

Proud to help you

Answer 2

Answer:

Answer is given above.