SOLUTION: I'm trying to plot points on a graph. the problem is y=3sec4x. I have all the points but one. I'm stuck at 5 pi/2. I have no idea how to find this on the unit circle. Explain plz?

Algebra ->  Trigonometry-basics -> SOLUTION: I'm trying to plot points on a graph. the problem is y=3sec4x. I have all the points but one. I'm stuck at 5 pi/2. I have no idea how to find this on the unit circle. Explain plz?      Log On


   

Question 194801: I'm trying to plot points on a graph. the problem is y=3sec4x. I have all the points but one. I'm stuck at 5 pi/2. I have no idea how to find this on the unit circle. Explain plz?
Found 2 solutions by solver91311, stanbon:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


From the positive x-axis to the positive y-axis: , then from the positive y-axis to the negative x-axis another for a total of . Then one more quarter circle, . All the way back to the beginning: . Yep, is the same thing as . In fact, all angles of the form are the same angle


John

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
I'm trying to plot points on a graph. the problem is y=3sec4x. I have all the points but one. I'm stuck at 5 pi/2. I have no idea how to find this on the unit circle. Explain plz?
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Try cos(5pi/2) which is the same as cos(pi/2) = 0
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Since sec is the inverse of cos, sec(5pi/2) is undefined.
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Cheers,
Stan H.