I need help in a simple Vectors question?

Given that the non-zero vectors a and b are non-parallel and that
3a+t(2a-3b) = a+b+s(a+2b),
find the value of t and of s

1 Answer
Mar 19, 2018

#s = 4/7, t = -5/7#

Explanation:

If #vec a, vec b# are non parallel then from

#3 vec a+t(2 vec a-3vec b) = vec a+vec b+s(vec a+2 vec b)#

we conclude

#(2 +2t-s)vec a -(3t+1+2s) vec b = vec 0#

and then

#{(2 +2t-s=0),(3t+1+2s=0):}#

and solving gives

#s = 4/7, t = -5/7#