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In trig, you cannot just divide variable. Trig works very differently than Algebra.In other words, you can divide everything by x and end up with
In trig, you cannot just divide variable. Trig works very differently than Algebra.
And unless specified, by default trig uses radiant, not degree or gradiant.
Besides, when you're involving secant or sine functions in a mathematical equation, it probably means you're talking about angles.
If an angle is in radians, then you must put 'rad' after it to specify this. Angles have always been viewed as being 0 to 360 degrees: if an angle is not in degrees, then you must put the appropriate symbol after the number.Nope. Trig, be it in the context of Algebra or Calculus, is in radiant unless you put a degree notation.
If an equation calls for sin (12), you use radiant. Yon only use degree mode when it is written as sin (12 deg). In math, we operate trig as if we are talking about unit circle. For example, we express 180 deg as pi, and 90 deg as pi/2.
It is sort of like square root. If you don't put negative sign before the square root the answer is positive no matter what (principle of square root).
Example: squ(25) = 5, but -squ(25) = -5.
If an angle is in radians, then you must put 'rad' after it to specify this. Angles have always been viewed as being 0 to 360 degrees: if an angle is not in degrees, then you must put the appropriate symbol after the number.
If an angle is in radians, you must convert it to degrees before you can take the sine of it; give me the sine of 12 radians. And a gradient is a texture which is created by mixing two or more colors. And the square root example: if you don't put a subtraction symbol before any variable, it's assumed to be positive. If you put a negative symbol before the sine, then you'll be taking the inverse sine of that number. If you put a radian symbol after a number and a subtraction symbol before the number, then you will have
Dude, i dont wanna be a prick, but you clearly have no idea about what are you talking. Radians is an adimensional unit and its the standard measure in trigonometry. There is a reason why the perimeter of a circunference is 2Pi*r and not 2*360°*r
Also, no ? Take any decent calculator and put sin(90), awnsers will not be 1.
That may be, but the standard measurement when dealing with circles is degrees. (And 2π is 360 degrees)... And even though it is the standard measurement in trigonometry, you should still put 'rad' after it. And if I put the sine of 90 degrees into the calculator, it'll give me one answer and it better be one. Because the cosine of 90 degrees is 0. The circumference of a circle is equal to the degree times the radius. Since 2π is 360 degrees. And 2π/3 is 120 degrees. etc.
But I'd prefer not to answer any more statements since this thread might become locked because of it.
That may be, but the standard measurement when dealing with circles is degrees. (And 2π is 360 degrees)... And even though it is the standard measurement in trigonometry, you should still put 'rad' after it. And if I put the sine of 90 degrees into the calculator, it'll give me one answer and it better be one. Because the cosine of 90 degrees is 0. The circumference of a circle is equal to the degree times the radius. Since 2π is 360 degrees. And 2π/3 is 120 degrees. etc.
But I'd prefer not to answer any more statements since this thread might become locked because of it.
Just as others have pointed out - it is accepted that when talking about trigonometry you use radians unless specified otherwise. sin(90) is not the same as sin(90°). Could you please provide info on why you think it is otherwise? Did you study trigonometry in a different way?
Enter sin(90) into your calculator and then enter sin(90°). Then tell me what you get. I've said this before: radians must be converted to numeric degrees before you can take the sine of them. And it is not accepted: that's what your teacher tells you. Your teacher means that you should be able to convert degrees into radians and back again when dealing with a circle or any other geometric shape: get this through your thick skull.
Jeez, I'm getting blasted for solving a mathematical equation by using actual variables instead of writing a long paragraph. I didn't see any of you 'math experts' doing this.
Well since radians are the standard in calculus, then you've got to be able to convert them from degrees since degrees are used in all the other maths.The reason rads. are the standard is because, in calculus, degrees make everything complicated, for example, the Taylor series for sin(x) is:
http://upload.wikimedia.org/math/4/8/c/48c5cd3f92a3344fa1ee8e2b429d87a9.png (rads)
while in degrees is:
http://upload.wikimedia.org/math/0/2/0/0201271886336aedeb1480c16f85f1fd.png
Also, its obvious that your mathematical knowledge is null if you end canceling the X's in each side of an equation inside trigonometrical functions.