Q78: Use identities to simplify the expression.<br>-<img src="https://d2lvgg3v3hfg70.cloudfront.net/TB8458/.jpg"
Q79: Simplify the expression.<br>-<img src="https://d2lvgg3v3hfg70.cloudfront.net/TB8458/.jpg" alt="Simplify the expression.
Q80: Choose the expression which is equivalent to
Q81: Multiply and simplify.<br>-<img src="https://d2lvgg3v3hfg70.cloudfront.net/TB8458/.jpg" alt="Multiply and simplify.
Q82: Find the exact value using a double-angle
Q84: Determine whether the positive or negative sign
Q85: Choose the expression with exactly the same
Q86: Factor the trigonometric expression.<br>-<img src="https://d2lvgg3v3hfg70.cloudfront.net/TB8458/.jpg" alt="Factor the
Q87: Choose the expression which is equivalent to
Q88: Choose the equivalent expression for the given