Question

Show that the equation is not an identity by finding a value of x for which both sides are defined but not equal. cos x - cos x sinx = cos3 x

Answer 1

The answer is 0 because 180 degrees does not make a valid statement

Answer 2

Answer:

The answer is pi/4

Step-by-step explanation:

You substitute each x for "pi/4", you will see that the equation is incorrect, the two values are no longer equal.