If | A→ × B→ | = √3(A→ . B→)

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If | A^{^→} × B^{^→} | = √3(A^{^→} . B^{^→}) then the value of | A^{^→} + B^{^→} | is

1. (A² + B² + √3 AB)^{1 / 2}
2. (A² + B² + AB)^{1 / 2}
3. A² + B² + AB ^{1 / 2}
  √3
4. A + B

Correct Option: B

| A^{^→} × B^{^→} | = AB sin θ
A^{^→} . B^{^→} = AB cos θ
| A^{^→} × B^{^→} | = √3 (A^{^→} . B^{^→}) ⇒ AB sin θ = √3 AB cos θ
or , tan θ = √3
∴ θ = 60°
∴ | A^{^→} + B^{^→} | = √A² + B² + 2AB cos60°
= √A² + B² + AB

	A² + B² +	AB		^{1 / 2}
		√3