Help in finding the pronumerals of this equation

[duhherro]

it is k(i +j) = 3i - 2j +l(2i - j)

And we are working out what k and l is. (Vectors)

Thanks in advance!

[max payne]

Yeah you just expand and equate the coefficients
= ki + kj = (3+2l)i - (2+l)j
Therefore:
k = 3 + 2l _____(1)
K = 2 + l  _____(2)
 
And solve...

[duhherro]

Yeah you just expand and equate the coefficients
= ki + kj = (3+2l)i - (2+l)j
Therefore:
k = 3 + 2l _____(1)
K = 2 + l  _____(2)
 
And solve...

Ah thanks for that fast reply!!! I see now XD. TYVM

Also another question would be...

If a = 3i + j - k, find the vector b in the direction of a such that |b| = 5.

Have no idea how to do these type of questions :S

[Will T]

If you want to find vector b in the direction of vector a with a magnitude of 5 you need to find the unit vector in direction a and multiply it by 5.

a = 3i + j - k
Unit vector of a = (3i + j - k)/11^1/2
b = Unit vector of a x 5
b = 5(3i+j-k)/11^1/2