Establish the identity.cos(3x) = cos3 x - 3 sin2 x cos x
What will be an ideal response?
cos(3x) = cos(2x + x) = cos(2x) cos x - sin(2x) sin x = (cos2 x - sin2 x) cos x - 2 sin x cos x sin x = 
- sin2 x cos x - 2 sin2 x cos x = cos3 x - 3 sin2 x cos x.
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Find the domain and range and describe the level curves for the function f(x,y).f(x, y) = ln (3x + 3y)
A. Domain: all points in the xy-plane satisfying 3x + 3y > 0; range: all real numbers; level curves: lines 
B. Domain: all points in the xy-plane; range: all real numbers; level curves: lines 
C. Domain: all points in the xy-plane satisfying 3x + 3y > 0; range: real numbers z ? 0; level curves: lines 
D. Domain: all points in the xy-plane satisfying 3x + 3y ? 0; range: all real numbers; level curves: lines 
Graph the function.f(x) = e-x
A. 
B. 
C. 
D. 
Solve the equation by the method of your choice.7x2 = -12x - 2
A. 
B. 
C. 
D. 
Complete the table.
A. 
B. 
C. 
D. 