You have the following expression:
To verify the identity, you have that the left side of the equation becomes:
(1 + cosx)(1 - cosx) = (1 - cos^2 x)
because of the product of an expression by its conjugate result in a difference of squares. Or simplfy by expanding the factors and simplying.
Next, you have:
1 - cos^2 x = sin^2 x
because the Pythagorean identity.
Then, the identity is verified.
The path of the ball is an illustration of absolute equation.
The equation of the path is:
The given parameters are:
--- the vertex (i.e. the point where the ball hits the wall)
An absolute function is represented as:
Substitute
Substitute for x and y
Remove absolute bracket
Collect like terms
Solve for a
Simplify
Substitute in
Hence, the equation of the path is:
See attachment for graph that models the path
Read more about absolute equations at:
