Let `vec a= hat i` be a vector which makes an angle of `120^@` with a unit vector`vec b` in XY plane. then the unit vector `(vec a+ vec b)` is

Let `vec a= hat i` be a vector which makes an angle of `120^@` with a

1.	Let `vec a= hat i` be a vector which makes an angle of `120^@` with a unit vector`vec b` in XY plane. then the unit vector `(vec a+ vec b)` is
Answer» `OA = hat i` `OB = vec b_1 = -(cos 60^@)hat i + sin 60^@` `OB = vec b_2= - cos 60^@ hat i - sin 60^@ hat j` `vec a + vec b_1 = hat i - hat i/2 + sqrt3/2 hat j` `= 1/2 hat i + sqrt3/2 hat j` `vec a + vec b_2 = hat i - hat i/2 - sqrt3/2 hat j` `= 1/2 hat i - sqrt3/2 hat j` Answer

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Let `vec a= hat i` be a vector which makes an angle of `120^@` with a unit vector`vec b` in XY plane. then the unit vector `(vec a+ vec b)` is

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