Section 2.3 The Sine and Cosine Functions

11 Section 2.3 The Sine and Cosine Functions

a. $\sin (\frac{13 π}{4})$

b. $\sin (- \frac{7 π}{6})$

c. $\cos (\frac{14 π}{3})$

d. $\sin (\frac{15 π}{4})$

e. $\cos (\frac{13 π}{3})$

f. $\cos (- \frac{5 π}{6})$

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Answers

a. $- \frac{\sqrt{2}}{2}$

b. $\frac{1}{2}$

c. $- \frac{1}{2}$

d. $- \frac{\sqrt{2}}{2}$

e. $\frac{1}{2}$

f. $- \frac{\sqrt{3}}{2}$ .

2. Find four different values for:

a. $t$ for $\sin (t) = - \frac{1}{2}$ .

b. $t$ for $\cos (t) = \frac{\sqrt{3}}{2}$

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Answers

a. While there are infinite answers to this, here are some examples:

$- \frac{5 π}{6}, - \frac{π}{6}, \frac{7 π}{6}, \frac{11 π}{6}, \frac{19 π}{6}, \frac{23 π}{6} . . .$

b. While there are infinite answers to this, here are some examples:

$- \frac{π}{6}, - \frac{11 π}{6}, \frac{π}{6}, \frac{11 π}{6}, \frac{13 π}{6}, \frac{23 π}{6} . . .$