Let a = (x, 1), B = (4, x), and a and B have opposite directions, then the value of X is______ ．

Let a = (x, 1), B = (4, x), and a and B have opposite directions, then the value of X is______ ．

∵ vector a = (x, 1), B = (4, x), and the direction of a and B is opposite, let a = λ B, then λ < 0, ∵ (x, 1) = λ (4, x), that is, x = 4, λ 1 = λ x {x2 = 4, the solution is x = - 2, x = 2 (rounding off), and the value of ∵ x is - 2. So the answer is - 2

If the vectors a = (x, 1) and B = (4, x) are collinear and in the same direction, then X=

According to the meaning of the title
x/4=1/x
x²=4
X = 2 or x = - 2
Because the direction is the same, then
x>0
therefore
x=2