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प्रश्न
If in ΔABC, `vec(BA) = 2veca` and `vec(BC) = 3vecb`, then `vec(AC)` is ______.
विकल्प
`2veca + 3vecb`
`2veca - 3vecb`
`3vecb - 2veca`
`-2veca - 3vecb`
उत्तर
If in ΔABC, `vec(BA) = 2veca` and `vec(BC) = 3vecb`, then `vec(AC)` is `underlinebb(3vecb - 2veca)`.
Explanation:
By triangle law of vector addition,
`vec(AC) = vec(AB) + vec(BC)`
`vec(AC) = -vec(BA) + vec(BC)`
= `-2veca + 3vecb`
= `3vecb - 2veca`
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