Area Under Sine Wave: Anti Diff of -cosx

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In summary, when finding the area under a sine wave from 0 degrees to 90 degrees, taking the anti-differentiation of -cosx will give the area under the graph assuming the angle is in radians. This is because in a simplified sense, the derivative of sin x is cos x and the derivative of cos x is -sin x, but these definitions may differ in more advanced mathematics where t is not necessarily an angle. The unit for the area under the sine wave is one radian squared.
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philrainey
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A little question when working out the area under a sin wave from 0 degrees to 90 degrees or some lower angle if you take the anti diff of -cosx, does that give the area under the graph assumming the angle is in radians? so enter -cos90=0 subtract -cos0 or-1 the area under the sine wave is 0--1 or one unit (what is this unit) one radian squared?
 
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Yes, in a simplified sense, d(sin x)dx = cos x and d(cos x)/dx= -sin x are only true if x is in radians.

I say "in a simplified sense" because the ways in which sin(t) and cos(t) are defined in more advanced mathematics, t is not an angle at all.
 

1. What is the concept of "Area Under Sine Wave"?

The area under a sine wave refers to the total space enclosed by the curve of a sine function and the x-axis. It represents the total displacement of the wave over a given interval.

2. How is the area under a sine wave related to the function of -cosx?

The function of -cosx represents the derivative of the sine function. Taking the anti-derivative of -cosx will give us the original function, which is the sine wave. Therefore, the area under the sine wave can be determined by taking the anti-derivative of -cosx.

3. Why is the area under a sine wave important in mathematics and science?

The area under a sine wave has many applications in mathematics and science. It is used in calculating the displacement, velocity, and acceleration of objects in simple harmonic motion. It is also used in calculating the total energy and power of oscillating systems.

4. How do you calculate the area under a sine wave?

To calculate the area under a sine wave, you can use integration techniques. First, determine the limits of integration, which are the starting and ending points of the interval. Then, take the anti-derivative of -cosx, which is sinx, and evaluate it at the limits of integration. Finally, subtract the lower limit from the upper limit to get the area under the curve.

5. Is the area under a sine wave always positive?

No, the area under a sine wave can be positive or negative, depending on the limits of integration. If the limits are both positive or both negative, then the area will be positive. However, if the limits are on opposite sides of the x-axis, then the area will be negative.

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