Decide if each of the following equations is always true, sometimes true, or never true. If an equation 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).
Substitute values into the equations for
Are they always equal?
Is this always true?
If not, what values of
would make it true?