1. The problem states: Verify if $1+1=3$. 2. The formula for addition is $a+b=c$, where $a$ and $b$ are numbers and $c$ is their sum. 3. Applying the formula: $1+1=2$. 4. Since $2 \neq 3$, the statement $1+1=3$ is false. 5. Therefore, $1+1$ equals $2$, not $3$.