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

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What are the possible values for the angle?In summary, the solutions for sin(x)=0 and cos(x)=0 are x=0, pi, 2pi and x=pi/2, 3pi/2 respectively. This is because sine and cosine functions are periodic with a period of 2pi, meaning they repeat themselves every 2pi. Therefore, there are infinitely many solutions for these equations. They can also be found by looking at the domains of the functions from their graphs.
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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?
 
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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.
 

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

What are the zeros of sine and cosine?

The zeros of sine and cosine are the values of x for which the function equals zero. These values occur at every multiple of pi for sine, and every multiple of pi/2 for cosine.

How do I find the zeros of sine and cosine?

To find the zeros of sine and cosine, set the function equal to zero and solve for x. You can use algebraic methods or a graphing calculator to find the values of x where the function crosses the x-axis.

What is the relationship between the zeros of sine and cosine?

The zeros of sine and cosine are related by a phase shift of pi/2. This means that the zeros of cosine occur at the same x-values as the zeros of sine, but shifted by pi/2.

Can the zeros of sine and cosine be negative?

Yes, the zeros of sine and cosine can be negative. Since the sine and cosine functions are periodic, their zeros will repeat infinitely in both positive and negative directions on the x-axis.

Why are the zeros of sine and cosine important?

The zeros of sine and cosine are important because they help us find the solutions to trigonometric equations and understand the behavior of these functions. They also have many applications in fields such as engineering, physics, and astronomy.

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