cos(60) = 0.5 The simplest way is to use a calculator.
5400
using the unit circle, sin 30 + cos 60 - 2tan 45 can be solved as follows: = sin 30 + cos 60 - 2tan 45 = [1/2] + [1/2] - [2(1)] = 1 - 2 = -1
Using the cosine ratio: 2*cos(60) = 1 Answer: 1 foot
Cos times Cos
sin(30) = sin(90 - 60) = sin(90)*cos(60) - cos(90)*sin(60) = 1*cos(60) - 0*sin(60) = cos(60).
cos(60) = 0.57 x 60 x cos(60) = 7 x 30 = 210
cos(60) = -0.95241298
cos(60) = 0.5 The simplest way is to use a calculator.
I can answer if you tell me what cos means.
cos(195) = cos(180 + 15) = cos(180)*cos(15) - sin(180)*sin(15) = -1*cos(15) - 0*sim(15) = -cos(15) = -cos(60 - 45) = -[cos(60)*cos(45) + sin(60)*sin(45)] = -(1/2)*sqrt(2)/2 - sqrt(3)/2*sqrt(2)/2 = - 1/4*sqrt(2)*(1 + sqrt3) or -1/4*[sqrt(2) + sqrt(6)]
cos 60
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.
cos60= 1/2 sin60=1.732/2
5400
3/cos(60) = 6 units in length