Solving for y in Trigonometric Functions | Radian Question

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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 [itex]sin(2\pi)= 0[/itex] and [itex]cos(3\pi)= -1[/itex].

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.