SOLUTION: how do you sketch the graph of the indicated trigonometric or circular function y=3+4cos5(Θ-10°)

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Question 941246: how do you sketch the graph of the indicated trigonometric or circular function y=3+4cos5(Θ-10°)
Answer by Edwin McCravy(20062) About Me  (Show Source):
You can put this solution on YOUR website!

y%22%22=%22%22D%2BA%2Acos%28B%5E%22%22%28theta%2BC%29%29
y%22%22=%22%22D%2BA%2Asin%28B%5E%22%22%28theta%2BC%29%29

To find the 5 most important points,
1. Calculate 90°/B.
2. Begin with -C
3. Add what you got for step 1, 4 times to get the x-coordinants.
4. Substitute these in the original to get the y-coordinates.

y%22%22=%22%223%2B4cos%285%5E%22%22%28theta-%2210%B0%22%29%29

To find the 5 most important points,
1. Calculate 90°/5 = 18°.
2. Begin with -(-10°) = 10°
3. Add 18° 4 times to get the x-coordinants
   10°, 28°, 46°, 64°, 82°
4. Substitute in the original equation to get the y-values
   7,3,-1,7,3

Plot the 5 points (10°,7), (28°,3), (46°,-1), (64°,3), (82°,7)



[The computer labels the points on the x-axis above in a crazy way,
You should label your x-axis with the x-coordinates of the 5 points.]

Edwin