Evaluate the expression
cos(30°)=

Step-by-step explanation:

By using the cos square identity in trigonometry i.e., cos2ϴ = 1 – sin2 ϴ, we can evaluate the exact value of cos(33 ). For calculating the exact value of cos(∏/6), we have to substitute the value of sin(30°) in the same formula.

cos(30°) = √1 – sin230°

The value of sin30° is 1/2 (Trigonometric Ratios)

cos(30°) = √1 – (1/2)2

cos(30°) = √1 – (1/4)

cos(30°) = √(1 * 4 – 1)/4

cos(30°) = √(4 – 1)/4

cos(30°) = √3/4

Therefore, cos(30°) = √3/2

Step-by-step explanation:

cos 30° is √3 /2

Also refer to the image attached

the last choice

step-by-step explanation:

.632

step-by-step explanation:

6 * 1/10 = 3/5

3*0.01 = 0.03

3/5 + 0.03 = .63

2*0.002 = .002

.63 + 0.002 = .632