Answer:
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
The value is 2+3 hope this helps ok good not luck
Answer:D
Step-by-step explanation:
It’s D for sure
Answer:
30 mph
Step-by-step explanation:
time = distance/speed
If x represents Jane's speed along the summit then her total exploration time is ...
12/x + 40/(x -5) = 2 . . . . . hours
Multiplying by (x)(x -5), we get ...
12(x -5) +40(x) = 2(x)(x -5)
Dividing by 2 and subtracting the left side gives ...
x^2 -31x +30 = 0
(x -30)(x -1) = 0 . . . . . factor
Solutions are x = 30 and x = 1, values of x that make the factors zero. A speed of 1 mph makes no sense in this problem, so ...
Jane's speed along the summit was 30 mph.
If we let be the number of pages read in 1 hour, then in 7 hours Doug reads pages. We know that this number of pages is 231, so we have