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Need help finding the exact value of sec pi/3

User JD Hernandez
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2 Answers

25 votes
25 votes

Final answer:

The exact value of sec(pi/3) is 2.

Step-by-step explanation:

The question asks for the exact value of sec(pi/3).



We know that the secant function is the reciprocal of the cosine function.



To find the exact value of cos(pi/3), we can use the unit circle.



  1. Start by drawing a circle with a radius of 1 unit.
  2. Divide the circle into six equal parts.
  3. The angle pi/3 corresponds to one of these parts.
  4. At this angle, the x-coordinate of the point on the unit circle is 1/2 and the y-coordinate is sqrt(3)/2.
  5. The cosine function is defined as the x-coordinate, so cos(pi/3) = 1/2.



Now, since sec(x) = 1/cos(x), we can find the value of sec(pi/3) by taking the reciprocal of cos(pi/3). Therefore, sec(pi/3) = 1/(1/2) = 2.

User ZdaR
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2.6k points
23 votes
23 votes

Solution:

Given:


sec((\pi)/(3))

To find the exact value,

Step 1: Apply the trigonometri identieties.

From the trigonometric identities,


sec\text{ }\theta\text{ =}(1)/(cos\theta)

This implies that


sec((\pi)/(3))=(1)/(\cos((\pi)/(3)))

Step 2: Evaluate the exact value.


\begin{gathered} since \\ \cos((\pi)/(3))=(1)/(2), \\ we\text{ have} \\ sec((\pi)/(3))=(1)/(\cos(\pi\/3))=(1)/((1)/(2))=2 \end{gathered}

Hence, te exact value of


sec((\pi)/(3))

is evaluated to be 2

User Jeremiah Stillings
by
2.8k points