Calculating 2A + 3(B+C): Vector Addition

AI Thread Summary
To calculate 2A + 3(B+C) with vectors A, B, and C, first compute 2A as (4, -2, 2). Next, add vectors B and C to get (4, 4, 3), then multiply by 3 to obtain (12, 12, 9). Adding these results gives (16, 10, 11) for 2A + 3(B+C). The method used is correct, as scalar multiplication simply scales the vector's magnitude while maintaining its direction. The discussion confirms that this approach adheres to vector addition and scalar multiplication rules.
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vector A= (2,-1,1)
vec. B = ( 3, 0, 5)
vec. C = (1,4,-2)
what is 2A + 3(B+C)

this is what i did:
2A = 2(2,-1,1) = (4,-2, 2)

(B+C) = (4,4,3) x 3 = (12,12, 9)

2A + 3(B+C) = (16,10,11)

is this the correct way to think and do this problem?
 
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Yes, you just add up the components because all vectors are the sum of their components; and of course, a scalar times a vector is just a vector of scaled up magnitude in the direction of the original vector.
 
okay thank you! and is it all right to multiply like that? or is there some other rule for multiplying vectors?
 
It is all right, because that is just a case of a scalar multiplying a vector.
 
ok! thank you very much!
 
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