Solve the equation. And write all solutions in general form.
Answers
Answer:
x = pi/2 + 2 pi n x = pi + 2 pi n where n is an integer
x = 5pi /3 + 2 pi n
Step-by-step explanation:
8 cos^2 x + 4 cos x-4 = 0
Divide by 4
2 cos^2 x + cos x-1 = 0
Let u = cos x
2 u^2 +u -1 =0
Factor
(2u -1) ( u+1) = 0
Using the zero product property
2u-1 =0 u+1 =0
u = 1/2 u = -1
Substitute cosx for u
cos x = 1/2 cos x = -1
Take the inverse cos on each side
cos ^-1(cos x) = cos ^-1(1/2) cos ^-1( cos x) =cos ^-1( -1)
x = pi/2 + 2 pi n x = pi + 2 pi n where n is an integer
x = 5pi /3 + 2 pi n
Related Questions
In a climate survey, it was determined that in a random sample of 15 days, the average temperature in Kalamazoo at 2:00 PM in the months of July and August is 73.38 degrees with a standard deviation of 3.798 degrees. Using this information, a 95% confidence interval for the average is (71.28, 75.48). Which of the following is the appropriate interpretation of this interval?1)We are certain that 95% of the days in the months of August and July will have a temperature at 2:00 PM between 71.28 and 75.48.2)We cannot determine the proper interpretation of this interval.3)We are 95% confident that the average daily temperature for the months of July and August at 2:00 PM for the days recorded is between 71.28 and 75.48.4)We are 95% confident that the proportion of all days' temperatures will fall between 71.28 and 75.48.5)We are 95% confident that the average daily temperature for the months of July and August at 2:00 PM is between 71.28 and 75.48.
An above-ground swimming pool in the shape of a cylinder has a diameter of 16 feet and a height of 5 feet. If the pool is filled with water to 1.5 inches from the top of the pool, what is the volume, to the nearest cubic foot, of the water in the pool?⇆
Help me please. Best answer gets brainliest.
Find the absolute maximum and minimum values of the function over the indicated interval, and indicate the x-values at which they occur. f (x )equals8 x minus 5 (A) [0,4] (B) [negative 4 comma 3 ]
B.hotter
C.colder
D. Wetter
Answers
Answers
Answer:
D) {-1}
Step-by-step explanation:
A rational expression is "not defined" when its denominator is zero. Hence to find values of x that make the expression "not defined," you solve the equation ...
denominator = 0
2x +2 = 0 . . . . . . put the actual denominator into the equation
x + 1 = 0 . . . . . divide by 2
x = -1 . . . . . . . . subtract 1
The expression is "not defined" for x in the set {-1}.
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11 members and we have to pick three without replacement.
= 165
There are 165 possible sets of officers
Answers
Answer:
SAS
Step-by-step explanation:
You have two pairs of congruent sides that are congruent.
The included angles are vertical angles, so they are congruent.
That means you have two sides and the included angle in each triangle.
Answer: SAS
Answers
Answer:
2
Step-by-step explanation:
3/8 = 2/8,1/4
A. -4/5
B. 4/3
C. -3/5
D. 4/5
Answers
Answer:
A
Step-by-step explanation:
The cosine of a right triangle is the adjacent over the hypotenuse. If the cosine is -3/5 then it must be a right triangle with sides 3, 4, & 5 since this is a Pythagorean triple. This means the sin will be -4/5. We know its negative because the tangent is positive so this is the 3rd quadrant where both Sine and Cosine are negative.