if the sum of two unit vectors is a unit vector, then the magnitude of their difference is(a) sq root of 3(b) sq root of 2(c) sq root of 5(d) 1/sq root of 2i wanted the solution alsowaiting for ur reply

let two vectors are a,b then

resultant of sum = (a² + b² + 2abcos@)^1/2 = 1               (given)

a = b = 1          (unit vector)

 1+1+2cos@ = 1

      cos@ = -1/2           .................1

now resultant of difference = magnitude (a-b)

R = (a² + b² - 2abcos@)^1/2

a = b = 1 , cos@ = -1/2 so

R = [ 1+1+1]^1/2 = root3

option a) is correct

thanks bro

sq root of 3