Update - the question is similar to this one:

https://www.coursehero.com/u/file/33766339/MAT-140-Milestone-Twodocx/#/doc/qa

But the formula is different: I'm trying to prove the identity for cos(x-y)/cos x siny = 1+tan x tan y

and indicate the steps on the prompt section.

Overview: For the final project, you will illustrate your process for solving selected precalculus problems. In this way, you will defend the validity of your solutions and demonstrate your ability to effectively communicate using precalculus notations, conventions, and terminology. In this milestone, you will submit your first practice problem walkthrough. You will solve a similar trigonometric functions problem as the one that you will ultimately need to address in your final project. This is an important opportunity to practice "walking through" a problem solution in order to gain feedback prior to submitting your final project.

Identity:

sin(xy)/cosxsiny=tanxcoty1

Prompt: Use the provided template to complete the trigonometric identity proof above and illustrate your process by addressing each of the following elements:

I. Indicate each step of your process in the "Statement" column.

A. Identify the problem statement.

B. Correctly use the identities and/or theorems.

C. Correctly use the algebraic process.

D. Identify the final statement.

II. Defend your process by identifying the appropriate explanation for each process step in the "Rule" column.

Statement Rule

*Use this template to indicate your answer. Defend your process by identifying the appropriate explanation for each process step in this column.

You can create more rows if necessary.

Indicate each step of your process in this column