If |A→+B→| = |A→−B→|, then the angle between A→  and B→ will be

Let θ be the angle between the vectors A→ and B→.Then |A→ + B→| = A2+B2+2ABcosθ|A→ − B→| = A2+B2-2ABcosθ|A→ + B→| = |A→ − B→| ∴  A2+B2+2ABcosθ = A2+B2-2ABcosθSquaring on both sides, we getA2+B2+2ABcosθ = A2+B2-2ABcosθ4ABcosθ = 0∴ cosθ = 0 or θ = π2