Solving $x + 3^x < 4$ analytically
$x+3^{x}$ is a continuous strictly increasing function. Hence $\{x: x+3^{x}<4\}=(-\infty, t)$ where $t$ is the unique real number $t$ such that $t+3^{t}=4$. Note that $t=1$!
Solving $x + 3^x < 4$ analytically
$x+3^{x}$ is a continuous strictly increasing function. Hence $\{x: x+3^{x}<4\}=(-\infty, t)$ where $t$ is the unique real number $t$ such that $t+3^{t}=4$. Note that $t=1$!