I assume you're asked to solve
4 cos²(<em>x</em>) - 7 cos(<em>x</em>) + 3 = 0
Factor the left side:
(4 cos(<em>x</em>) - 3) (cos(<em>x</em>) - 1) = 0
Then either
4 cos(<em>x</em>) - 3 = 0 <u>or</u> cos(<em>x</em>) - 1 = 0
cos(<em>x</em>) = 3/4 <u>or</u> cos(<em>x</em>) = 1
From the first case, we get
<em>x</em> = cos⁻¹(3/4) + 2<em>nπ</em> <u>or</u> <em>x</em> = -cos⁻¹(3/4) + 2<em>nπ</em>
and from the second,
<em>x</em> = <em>nπ</em>
where <em>n</em> is any integer.
Answer
- 3/2
Step-by-step explanation:
Hope this helps:) if you need anynore help lmk!
Answer:
89 rooms should be set for early book customer
Step-by-step explanation:
According to the given data we have the following:
OVERAGE(CO) = 200
SHORTAGE(CS) = 500
In order to calculate how many rooms should be set for early book customer we would have to use the following formula:
OPTIMAL BOOKING = MEAN + (Z * STDEV)
MEAN = 75
STDEV = 25
SERVICE LEVEL= CS / (CS + CO) = 500 / (500 + 200) = 0.7143
Z VALUE FOR 0.7143 = 0.57
OPTIMAL BOOKING = 75 + (0.57 * 25) = 89
89 rooms should be set for early book customer
Complete the square to rewrite the quadratic:
2 <em>x</em>² + 3 <em>x</em> + 5 = 2 (<em>x</em>² + 3/2 <em>x</em>) + 5
... = 2 (<em>x</em>² + 3/2 <em>x</em> + 9/16 - 9/16) + 5
... = 2 (<em>x</em>² + 3/2 <em>x</em> + (3/4)²) + 5 - 9/8
... = 2 (<em>x</em> + 3/4)² + 31/8
Any real number squared becomes non-negative, so the quadratic expression has a minimum value of 31/8, which is greater than 0, and so there are no (real) <em>x</em> for which <em>y</em> = 0.