Why are 0 and pi/2 the solutions for sin(x)=0 and cos(x)=0?

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Discussion Overview

The discussion centers around the solutions to the equations sin(x) = 0 and cos(x) = 0, specifically exploring why x = 0, π, 2π are solutions for sin(x) = 0 and x = π/2, 3π/2 for cos(x) = 0. The scope includes conceptual understanding and reasoning behind these solutions, as well as the periodic nature of the sine and cosine functions.

Discussion Character

  • Conceptual clarification
  • Exploratory

Main Points Raised

  • Some participants note that sin(x) = 0 has solutions at x = 0, π, 2π, while cos(x) = 0 has solutions at x = π/2, 3π/2.
  • Others point out that there are more solutions due to the periodic nature of sine and cosine functions, which repeat every 2π.
  • A participant expresses a desire to understand the reasoning behind these solutions and questions whether they can be derived from the graphs of the functions.
  • One participant suggests visualizing the problem by drawing a triangle and considering the angles formed when the adjacent or opposite side is zero.

Areas of Agreement / Disagreement

Participants generally agree on the basic solutions for sin(x) = 0 and cos(x) = 0, but there is no consensus on the method for deriving these solutions or the understanding of their periodic nature.

Contextual Notes

Some participants reference the graphs of sine and cosine functions as a means to understand the solutions, but there is no detailed exploration of the mathematical steps involved in deriving these values.

Ric-Veda
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Just a quick question, I was solving sin(x)=0 and cos(x)=0. I was trying hard to find out the solutions and the solutions were: for sin(x)=0------>x=0, pi, 2pi for cos(x)=0-------->x=pi/2, 3pi/2

But my question is why are those the solutions?
 
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Ric-Veda said:
Just a quick question, I was solving sin(x)=0 and cos(x)=0. I was trying hard to find out the solutions and the solutions were: for sin(x)=0------>x=0, pi, 2pi for cos(x)=0-------->x=pi/2, 3pi/2

But my question is why are those the solutions?

There are more solutions! (sin and cos are periodic functions and repeat itself every ##2\pi##)
 
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Math_QED said:
There are more solutions! (sin and cos are periodic functions and repeat itself every ##2\pi##
But I want to know the whole step. Do I get the values by just looking at their domains from their graphs?
 
Thread moved from Precalc Homework section. @Ric-Veda, if you post in the Homework & Coursework sections, like you originally did with this thread, you must use the homework template.

Since you've posted other questions about Laplace transforms and differential equations, it's a reasonable expectation that you have some familiarity with trig functions. If not, you really need to spend some time reviewing them.

As already mentioned, the sine and cosine functions are periodic. Take a look at the graphs of these functions, which should make it obvious that there are many (infinitely many) solutions to sin(x) = 0 and cos(x) = 0.
 
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Ric-Veda said:
But I want to know the whole step. Do I get the values by just looking at their domains from their graphs?
Try drawing a triangle and imagine the angle formed when the adjacent or opposite side is 0.
 

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