Finding a mathematical model that disproves a sequent's validity

Question

I want to show that the sequent $$ \forall x(R(x)\rightarrow Q(x))\vdash\forall x(R(x)\vee Q(x)) $$ is invalid, by finding a mathematical model where the LHS of the $\vdash$ evaluates to TRUE and the RHS of the $\vdash$ evaluates to FALSE.

However, the mathematical models that I have come up with so far show that the sequent is TRUE on both sides of the $\vdash,$ for example,

Let the Universe be $x\in \mathbb{Z}^+,$
$R(x)$ can be interpreted as "$x$ is a multiple of 4",
$Q(x)$ can be interpreted as "$x$ is a multiple of 2".

How to approach this question?

Answer 1

$$∀x(R(x)→Q(x))⊢∀x(R(x)∨Q(x))$$

To make the main antecedent true, we can try letting $R$ be a contradiction.

Then, to additionally make the main consequent false, it makes sense to let $Q$ also be a contradiction.

Can you take it from here?