Solving for y in Trigonometric Functions | Radian Question

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The discussion revolves around solving the function y = sin(2x) + cos(3x) for specific values of x and determining its period. For x = π, y can be calculated as sin(2π) = 0 and cos(3π) = -1, resulting in y = -1. For x = 0.3 radians, users are advised to use a calculator for an accurate value. The period of sin(2x) is π radians, while the period of cos(3x) is 2π/3 radians, with the overall period being the least common multiple of these two values. Understanding these calculations is essential for working with trigonometric functions in radians.
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Homework Statement


Consider the function y=sin2x +cos3x.

a.] Find a Value for the y if x= pye [Or who how ever it is spelled. 3.141592654]

b.] Find y if x=0.3 Radians.

c.] What is a period of this function? Show how you obtain this answer.

The Attempt at a Solution



No attempt since I have never come across these types of question in Radians before.
 
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Hi Venito! :smile:

(have a pi: π :wink:)
Venito said:
No attempt since I have never come across these types of question in Radians before.

π radians = 180º …

if you're not used to radians, do it in degrees, and convert using the 180/π factor. :wink:
 
I am use to radians. Just not these. So use degrees. Okay I will give it a try.

Thanks.
 
The period of sin(2x) is π radians. The period of cos(3x) is 2π/3 radians. The period of the sum of these two functions is the smallest interval that is evenly divisible by both π and 2π/3.

By the way, we spell the name of this Greek letter as pi. I'm guessing that you're Italian, and it is spelled the same way in Italian.
 
Venito said:

Homework Statement


Consider the function y=sin2x +cos3x.

a.] Find a Value for the y if x= pye [Or who how ever it is spelled. 3.141592654]
You certainly should know that sin(2\pi)= 0 and cos(3\pi)= -1.

b.] Find y if x=0.3 Radians.
This is not going to be any simple value. Use a calculator.

c.] What is a period of this function? Show how you obtain this answer.
What is the period of sin(2x)? What is the cos(3x)? What is the least common multiple of those two periods? Do you see why that is the period of y?

The Attempt at a Solution



No attempt since I have never come across these types of question in Radians before.
 
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