(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Given that c= 3i + 4j and d= i - 2j

find μ when μc + d is parallel to i +3j

2. Relevant equations

3. The attempt at a solution

3iμ + 4jμ + i + j

i( 3μ + 1) + (4μ -2) j

since it is parallel to i + 3j therefore3μ+1=3(4μ-2)

giving μ = 7/9

However μ = -1

Additional information:

Apparently (see bold) I am supposed to multiply the LHS by 3 instead of the RHS but by equating I and J vectors and looking at the parallel line it would seem logical to do it the way I have (or am I being retarded?). I can accept that I have the multiply LHS instead of RHS but I don't understand why!!

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# Homework Help: Finding unknown given vector a,b and parallel

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