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cos(30)cos(55)+sin(30)sin(55)=cos(30-55) = cos(-25)=cos(25)
Note: cos(a)=cos(-a) for any angle 'a'.
cos(a)cos(b)+sin(a)sin(b)=cos(a-b) for any 'a' and 'b'.
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What is the ratio of the cosine of an angle?
Fora right angle triangle: cosine angle = adjacent/hypotenuse
What is the cosine of a 60 degree angle?
60 degrees = 0.5 1/2
When you have a right angle what does the law of cosines reduce to?
cosine = adjacent/hypotenuse
What is the cosine of a 30 degree angle?
As a decimal: 0.866 As a fraction: √(3)/2
How do you find an angle using sine cosine tangent?
If you know the angle's sine, cosine, or tangent, enter it into the calculator and press <inverse> sine, cosine, or tangent. On MS Calc, in Scientific Mode, using Degrees, enter 0.5, then check Inv and the press sin. You should get 30 degrees. The other functions work similarly.
What is the ratio of the cosine of an angle?
Fora right angle triangle: cosine angle = adjacent/hypotenuse
What is the cosine function about?
The cosine function is mathematical equation to determine the adjacent angle of a triangle. The cosine of an angle is the ratio of the length of the hypotenuse: so called because it is the sine of the co-angle.
How is cosine defined?
In a right triangle, the cosine of an angle is defined as the ratio of the adjacent side of that angle to the hypotenuse.
How do you find the angle of a cosine?
You mean, you have the cosine, and want the angle? That is called arc-cosine, often written as cos-1x. Your scientific calculator should have a "shift" key or something similar, which you press, followed by the cosine key. That will give you the inverse cosine or arc-cosine.
What is a cosine ratio?
In a right angle triangle it is: cosine ratio = adjacent/hypotenuse
What is the cosine of a 59 degree angle?
cosine(59 degrees) = 0.51504 (rounded)
The tangent of an angle equals the ratio of the?
Sine of the angle to its cosine.
The tanget of an angle equals the ratio of the?
Sine and the cosine of the angle.
When is secant not defined?
The secant of an angle is the reciprocal of the cosine of the angle. So the secant is not defined whenever the cosine is zero That is, whenever the angle is a multiple of 180 degrees (or pi radians).
What angle is Sine and cosine equal?
at a 45 degree angle, or pi/4
If the tangent of an angle is 2 what is the cosine?
The cosine is ±1/sqrt(5) = ±0.4472 (approx).
If the cosine of B is 65 what is the angle?
Cosine cannot have this kind of high value, it ranges from -1 to +1
