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With usual notations, in any triangle AB...

With usual notations, in any triangle ABC, prove the following by vector method .
(i) ` a^(2)=b^(2)+c^(2)-2bc cos A `
(ii) ` b^(2)=c^(2)+a^(2)-2bc cosB `
(iii) ` c^(2)=a^(2)+b^(2)-2bc cosC `

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The correct Answer is:
` b^(2)+c^(2)-2bc cosA `
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FULL MARKS-APPLICATIONS OF VECTOR ALGEBRA-Additional Questions Solved
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