Decide if each of the following statements are always true, sometimes true, or never true. If a statement is always true, justify how you know; if it is sometimes true, give the exact values of
Simplify the part of the equation on the left side of the equals sign.
Does it equal the part on the right side?
Use the same method as part (a).
) cos( )
Substitute values into the equations for x.
Are they always equal?
Is this always true?
If not, what values of
would make it true?