cos(195) = -0.965925826289
cos(120 = -0.5
Cos(120) = -0.5
A Quadrantal angle is an angle that is not in Quadrant I. Consider angle 120. You want to find cos(120) . 120 lies in quadrant II. Also, 120=180-60. So, it is enough to find cos(60) and put the proper sign. cos(60)=1/2. Cosine is negative in quadrant II, Therefore, cos(120) = -1/2.
The inexact value of tan 330 is -0.577350, to six significant places. The exact value cannot be represented as a single number because it is a non terminating decimal. To represent it exactly, consider that tan x is sin x over cos x, and that sin 330 is -0.5 and cos 330 is square root of 0.75. As a result, the exact value of tan 330 is -0.5 divided by square root of 0.75.
cos(195) = -0.965925826289
cos(120 = -0.5
It is: cos(15) = (sq rt of 6+sq rt of 2)/4
The radical answer is sqrt(3)/2. (0.86602540378443864676372317075294)
The exact value is an irrational number, and can't be written on paper with digits.0.34202 is less than 0.000042 percent wrong.Cos(70 deg) is an irrational number and it is impossible to give its exact value.
1.25
Cos(120) = -0.5
A Quadrantal angle is an angle that is not in Quadrant I. Consider angle 120. You want to find cos(120) . 120 lies in quadrant II. Also, 120=180-60. So, it is enough to find cos(60) and put the proper sign. cos(60)=1/2. Cosine is negative in quadrant II, Therefore, cos(120) = -1/2.
A Quadrantal angle is an angle that is not in Quadrant I. Consider angle 120. You want to find cos(120) . 120 lies in quadrant II. Also, 120=180-60. So, it is enough to find cos(60) and put the proper sign. cos(60)=1/2. Cosine is negative in quadrant II, Therefore, cos(120) = -1/2.
The inexact value of tan 330 is -0.577350, to six significant places. The exact value cannot be represented as a single number because it is a non terminating decimal. To represent it exactly, consider that tan x is sin x over cos x, and that sin 330 is -0.5 and cos 330 is square root of 0.75. As a result, the exact value of tan 330 is -0.5 divided by square root of 0.75.
tan u/2 = sin u/1+cos u
The value of cos 40 degrees is approximately 0.766.