Establish the identity.cos (x - y) - cos (x + y) = 2 sin x sin y
What will be an ideal response?
cos (x - y) - cos (x + y) = cos x cos y + sin x sin y - ( cos x cos y - sin x sin y) = 2 sin x sin y.
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FASB's Statement of Financial Accounting Concepts No. 7 provides general principles governing the use of present value and the objectives of present value accounting measurements.
Answer the following statement true (T) or false (F)
Write the trigonometric expression as an algebraic expression in u.sin (tan-1 u)
A. u
B. 
C. 
D. 
Use the given stock table to answer the question.Based on the fact that stocks historically trade at an average P/E ratio of about 12-14, does the stock price of company ABC seem cheap, about right, or expensive right now? 
A. about right B. expensive C. cheap
Find the indicated sum.
A. 44 B. 70 C. 65 D. 30