Answer
The equivalent trigonometric form of $3 + 4i$ is $5cis53.13^\circ$ or $5(cos53.13^\circ + isin53.13^\circ)$.
Work Step by Step
For $3 + 4i$, the absolute value is $\sqrt{3^2 + 4^2} = 5$ and $\theta = arctan(\frac{4}{3}) = 53.13^\circ$, since $3 + 4i$ is in the 1st quadrant.
Therefore, the equivalent trigonometric form of $3 + 4i$ is $5cis53.13^\circ$ or $5(cos53.13^\circ + isin53.13^\circ)$.
