Prove the identity.
- 
= cos2 2x - sin2 2x
What will be an ideal response?
Answers may vary. One possible solution is:
- 
= cos 3x cos x - sin 3x sin x = cos (3x + x) = cos 4x = cos2 2x - sin2 2x.
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Use synthetic division to find the function value.f(x) = 2x3 + 4x2 - 3x + 6; find f(-3)
A. -207 B. -3 C. -105 D. -21
Solve the problem.An artifact is discovered at a certain site. If it has 59% of the carbon-14 it originally contained, what is the approximate age of the artifact to the nearest year? (carbon-14 decays at the rate of 0.0125% annually.)
A. 4720 years B. 1833 years C. 4221 years D. 3280 years
Begin by graphing the standard quadratic function f(x) = x2 . Then use transformations of this graph to graph the given function.h(x) = (
x - 2)2
A. 
B. 
C. 
D. 
Graph the function and y = cos x in the same rectangular system for 0 ? x ? 2?.y = 
cos x
A. 
B. 
C. 
D. 