Verify the identity.cos 
= -sin x
What will be an ideal response?
cos
= cos(x)cos
- sin(x)sin
.
Since cos
= 0 and sin
= 1, then cos
= cos(x)(0) - sin(x)(1) = -sin x.
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Consider a soldier facing in a given direction (say north). Let us denote "left face" by l, "right face" by r, "about face" by a, and "stand fast" by f. (The element f means "don't move from your present position." It does not mean "return to your original position.") Then we define 
and an operation 
meaning
"followed by." Thus, 
means "left face" followed by "left face" and is the same as the single command "about face." Complete the following table.
a l r f a 0 l a r 0 f ?
A. a l r f
a f r l a
l r f f l
r l f a r
f a l r f
?
B.
a l r fa r l a f
l l f l a
r a l r a
f f r a f
?
C.
a l r fa f r l a
l r a f l
r l f a r
f a l r f
?
D.
a l r fa r a f l
l a f a r
r f a r f
f l r f a
?
A sequence c0, c1, c2, . . . is defined as follows:
Provide an appropriate response.What rule is applied first to find the derivative of the functionf(x) = 
?
A. Quotient rule B. Power rule C. Product rule D. Square root rule
Solve.A 37-inch-square TV is on sale at the local electronics store. If 37 inches is the measure of the diagonal of the screen, use the Pythagorean theorem to find the length of the side of the screen to the nearest tenth of an inch.
A. 26.2 in. B. 3 in. C. 684.5 in. D. 6.1 in.