Prove 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 = 
= 
= 
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Solve using a matrix on a graphing calculator.
A. (4.2, 7.2, 3.9) B. (0.5, 0.9, 0.5) C. (2.1, 3.6, 1.9) D. (1.0, 1.8, 1.0)
Figure (a) shows a vacant lot with a 100-ft frontage in a development. To estimate its area, we introduce a coordinate system so that the x-axis coincides with the edge of the straight road forming the lower boundary of the property, as shown in Figure (b). Then, thinking of the upper boundary of the property as the graph of a continuous function f over the interval [0, 100], we see that the problem is mathematically equivalent to that of finding the area under the graph of f on [0, 100]. To estimate the area of the lot using a Riemann sum, we divide the interval [0, 100] into five equal subintervals of length 20 ft. Then, using surveyor's equipment, we measure the distance from the midpoint of each of these subintervals to the upper boundary of the property. These measurements give the
values of f(x) at x = 10, 30, 50, 70, and 90. What is the approximate area of the lot?
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__________ square feet
Fill in the blank(s) with the appropriate word(s).
The amount A of money on deposit for t years in an account earning simple interest is a linear function of t. Express that function as an equation if src="https://sciemce.com/media/3/ppg__cognero__2.1_Functions_and_Function_Notation__media__056bd241-9983-4839-834b-4e68f17e5e09.PNG" class="wirisformula" align="middle" style="vertical-align: middle;" data-wiris-created="true" varid="variable_id_field" variablename="impvar_5c6869e672c245bd9b9e6c04a" /> when 
when 
and 
.
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A. 
B. ?
C. ?
D. ?
E. 
Factor the polynomial.6z6 - 5z3 - 6
A. (3z3 + 2)(2z3 - 3) B. (3z3 + 1)(2z3 - 6) C. 6(z3 - 3)(z3 + 2) D. (2z3 + 3)(3z3 - 2)