Add, subtract, multiply, and divide both sides by the same thing
Note: Problems 10.1–10.3 refer to the trigonometric equation sin x + 1 = 0.
10.1 Identify the solutions to the equation on the interval 0 ≤ x < 2π.
To solve the equation sin x + 1 = 0 for x, you must first isolate the expression containing x on one side of the equal sign. Subtracting 1 from both sides of the equation accomplishes this task, isolating sin x on the left side of the equation.
When something is “isolated” it is all by itself. You want sin x to be all by itself on one side of the equation, but right now, there’s a “+ 1” next to it. Move that number to the other side of the equation by subtracting it from both sides.
sin x = –1
The problem instructs ...