Question

3. Find the value of $\cos\left(\frac{5\pi}{12}\right)$ using sum and difference formulas. Hint: Express $\frac{5\pi}{12}$ as the difference of two known angles. A) $\frac{\sqrt{2}-\sqrt{6}}{4}$ B) $\frac{-\sqrt{2}+\sqrt{6}}{4}$ C) $\frac{\sqrt{2}+\sqrt{6}}{4}$ D) $\frac{\sqrt{2}+\sqrt{6}}{2}$ E) $\frac{-\sqrt{2}-\sqrt{6}}{4}$ F) None of the above

          3. Find the value of $\cos\left(\frac{5\pi}{12}\right)$ using sum and difference formulas.
Hint: Express $\frac{5\pi}{12}$ as the difference of two known angles.
A) $\frac{\sqrt{2}-\sqrt{6}}{4}$
B) $\frac{-\sqrt{2}+\sqrt{6}}{4}$
C) $\frac{\sqrt{2}+\sqrt{6}}{4}$
D) $\frac{\sqrt{2}+\sqrt{6}}{2}$
E) $\frac{-\sqrt{2}-\sqrt{6}}{4}$
F) None of the above

3. Find the value of cos((5π)/(12)) using sum and difference formulas.
Hint: Express (5π)/(12) as the difference of two known angles.
A) (√(2)-√(6))/(4)
B) (-√(2)+√(6))/(4)
C) (√(2)+√(6))/(4)
D) (√(2)+√(6))/(2)
E) (-√(2)-√(6))/(4)
F) None of the above

Added by Jorge D.

Elementary and Intermediate Algebra

Alan S. Tussy, R. David Gustafson 5th Edition

Instant Answer

Solved by Expert Ankit Gupta

06/15/2020

Step 1

Step 1: We can express $\frac{5\pi}{12}$ as the difference of two known angles: $\frac{5\pi}{12} = \frac{2\pi}{3} - \frac{\pi}{4}$. Show more…

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3. Find the value of $cos(\frac{5\pi}{12})$ using sum and difference formulas. Hint: Express $\frac{5\pi}{12}$ as the difference of two known angles. A) $\frac{\sqrt{2}-\sqrt{6}}{4}$ B) $\frac{-\sqrt{2}+\sqrt{6}}{4}$ C) $\frac{\sqrt{2}+\sqrt{6}}{4}$ D) $\frac{\sqrt{2}+\sqrt{6}}{2}$ E) $\frac{-\sqrt{2}-\sqrt{6}}{4}$ F) None of the above