Use the addition formulas to derive the identity.cos 
= sin x
What will be an ideal response?
cos 
= cos x cos 
- sin x sin 
= cos x (0) - sin x (-1)
= 0 + sin x
= sin x
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Translate the argument into symbolic form. Then use a truth table to determine whether the argument is valid or invalid. (Ignore differences in past, present, and future tense.)If every student passes the quiz, then no review sessions are needed.
? Some review sessions are needed.
What will be an ideal response?
Use the basic trigonometric identities and the given information to find the exact values of the remaining trigonometric functions.tan ? = - 
and sec ? < 0
A. sin ? = 
cos ? = - 
tan ? = - 
csc ? = 
sec ? = - 
cot ? = - 
B. sin ? = 
cos ? = - 
tan ? = - 
csc ? = 
sec ? = - 
cot ? = - 
C. sin ? = - 
cos ? = 
tan ? = - 
csc ? = 
sec ? = 
cot ? = - 
D. sin ? = 
cos ? = - 
tan ? = - 
csc ? = 
sec ? = - 
cot ? = - 
Multiply.(-10)(0)(-8)(10)
A. -10 B. 0 C. 1 D. 10
Solve the problem.Halley's comet has an elliptical orbit with the sun at one focus. Its orbit shown below is given approximately by 
In the formula, r is measured in astronomical units. (One astronomical unit is the average distance from Earth to the sun, approximately 93 million miles.) 
Find the distance from Halley's comet to the sun at its shortest distance from the sun. Round to the nearest hundredth of an astronomical unit and the nearest million miles.
A. 64.11 astronomical units; 5963 million miles B. 12.03 astronomical units; 1119 million miles C. 6.02 astronomical units; 559 million miles D. 5.5 astronomical units; 511 million miles