Final answer:
To correctly identify the equation for the measure of ∠1, additional context or a diagram is needed as the information provided resembles equations used primarily in physics for analyzing two-dimensional collisions.
Step-by-step explanation:
To determine which equation is correct regarding the measure of ∠1 we need to consider the context of the problem. Often, these types of equations are related to motion or forces in physics. For instance, they could be referring to the conservation of momentum in the x- and y-axes separately during a collision.
Some of the equations provided resemble those used for analyzing collisions in two dimensions, involving the sine and cosine functions for the angles of the velocities pre- and post-collision. Without the specific context or a diagram, it is challenging to provide the correct equation for the measure of ∠1.
The provided equations suggest a scenario involving dynamics (motion) where angles and velocities (and possibly mass) play significant roles. Please provide additional information or clarification about the variables and the situation being described, so that a correct equation can be identified for ∠1.