All categories

3 years ago

Find all solutions to the equation. cos^2x + 2 cos x + 1 = 0

Mathematics

2 answers:

mixas84 [53]3 years ago

5 0

$\cos^2(x)+2\cos(x)+1=0\\\\ (\cos(x)+1)^2=0\\\\ \text{So:}\\\\ \cos(x)+1=0\\\\ \cos(x)=-1\\\\ \boxed{x=\pi+2k\pi},~k\in\mathbb{Z}$

Umnica [9.8K]3 years ago

5 0

Hope this helps you.

You might be interested in

What is the quotient of (x3 + 6x2 + 11x + 6) ÷ (x2 + 4x + 3)? x + 2 x – 2 x + 10 x + 6

evablogger [386]

Answer:

x + 2

Step-by-step explanation:

If we know one of the factors, we should be able to use long division.

We can divide the trinomial by the binomial and find the other factor.

x + 2

x² + 4x + 3)x³ + 6x² + 11x + 6

x³ + 4x² + 3x

2x² + 8x + 6

2x² + 8x + 6

Thus,

$\dfrac{x^{3} + 6x^2 + 11x + 6} {x^{2} + 4x + 3} = \mathbf{x + 2}$

6 0

3 years ago

one customer purchases 8 bags of dog food and 2 bags of dog food. The total weight of the purchases is 44 pounds. Another custom

Svetach [21]

68 pound of dog and cat food

6 0

3 years ago

"the life length x (in years) of a dvd player" is exponentially distributed with mean 5 years. what is the probability that a mo

loris [4]

The exponential distribution is:
$\lambda e^{- \lambda x}$
where $\lambda = \frac{1}{mean}=\frac{1}{5}$

The probability we want is how likely will a dvd player last more than 8 years, given it has already lasted 5 years
To find this, you use conditional probability.
$P(A|B) = \frac{P(A and B)}{P(B)}$
where A is P(x>8) and B is P(x>5)
To find these probabilities, integrate over the distribution:
$P(x \ \textgreater \ N) = \int_N^{\infty} \frac{1}{5} e^{-x/5} dx = e^{-N/5}$

Sub into conditional probability formula:

$P(x \ \textgreater \ 8 | x\ \textgreater \ 5) = \frac{P(x\ \textgreater \ 8)}{P(x\ \textgreater \ 5)} = \frac{e^{-8/5}}{e^{-5/5}} = e^{-3/5} = 0.549$

Final Answer: Given a dvd player is more than 5 years old, the probability that it will last another 3 more years is about 54.9%

3 0

3 years ago

Factor the expression completely -15t-6

Tema [17]

In order to factor this, we will need to take something out to get it to factor. Lets take out a greatest common factor, in this case our greatest common factor will be 3.
We will then write it as:

-3(5t+2)

8 0

2 years ago

Read 2 more answers

Total bill for the month was 551,

bulgar [2K]

Answer:

14) 2x + 13 = 21

Step-by-step explanation:

Have a nice day! :-)

5 0

2 years ago