The vector `vecA` and `vecB` are such that `|vecA+vecB|=|vecA-vecB|`. The angle between vectors `vecA` and `vecB` is -

Options

A. `90^(@)`
B. `60^(@)`
C. `75^(@)`
D. `45^(@)`

Answer

A

Explanation

`|vecA+vecB|=|vecA-vecB|rArr|vecA+vecB|^(2)=|vecA-vecB|^(2)`
`rArr A^(2)+B^(2)+2AB cos theta=A^(2)+B^(2)-2AB cos theta`
`rArr cos theta=0 rArr theta=90^(@)`