If →a⋅→b=0 and →a×→b=0 then which one of the following is correct?
Nonzero vectors →a,→b,→c satisfy →a.→b =0, (→b−→a).(→b+→c) = 0 and 2 |→b+→c|=|→b−→a|.
If = →a=μ→b+4→c then μ = ______