Complete the identity.sin 5x sin 8x cos 5x cos 8x = ?
A. 
B. cos2 80x
C. 
D. 
Answer: D
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Write a formula for a linear function f whose graph satisfies the conditions.Slope: - 
; y-intercept: 9
A. f(x) = - 
x + 9
B. f(x) = - 
x - 9
C. f(x) = 
x - 9
D. f(x) = 
x + 9
Solve the problem.Money magazine reports that the percentage of trading days in which the Dasdaq loses or gains 2% or more has been increasing since 1995 indicating more volatility in the Dasdaq. Use a graphing utility to fit an exponential function to the data. Predict the percentage of trading days in 2001 having such swings in value.
A. y = 1.669x1.706, 46 days B. y = 1.278e0.611x, 92 days C. y = 2.353e0.610x, 91 days D. y = 1.849e0.531x, 76 days
Find the nth term {an} of the geometric sequence. When given, r is the common ratio.3, 9, 27, 81, 243, ...
A. an = a1 + 3n B. an = 3 ? 3n-1 C. an = 3 ? 3n D. an = 3 ? 3n
Simplify the expression.
1/2
A. - 
B. 
C. - 
D. 