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2 years ago

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

Mathematics

1 answer:

Schach [20]2 years ago

4 0

$x= \pi$

Step-by-step explanation:

$\cos^2x+\cos x+1=0$

Let $u= \cos x$

Then $u^2+2u+1=(u+1)^2=0$

$\cos x = -1$

This gives us $x= \pi$ or all integer multiples of $\pi (n \pi)$

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With full explanation from the internet like before 3x2-6x+5=0

Elodia [21]

Answer:

$\sf x=1+i\sqrt{\dfrac{2}{3}} \ \quad and \quad \:x=1-i\sqrt{\dfrac{2}{3}}$

Explanation:

Given Expression:

3x² - 6x + 5 = 0

Use the Quadratic Formula:

$\sf x = \dfrac{ -b \pm \sqrt{b^2 - 4ac}}{2a} \ \ when \ \ ax^2 + bx + c = 0$

insert coefficients

$\Longrightarrow \sf x = \dfrac{-\left(-6\right)\pm \sqrt{\left(-6\right)^2-4\cdot \:3\cdot \:5}}{2\cdot \:3}$

$\Longrightarrow \sf x = \dfrac{\left6\right\pm \sqrt{-24} }{6}$

$\Longrightarrow \sf x = \dfrac{\left6\right\pm 2\sqrt{6}i}{6}$

$\Longrightarrow \sf x =1 \pm i\dfrac{\sqrt{6} }{3}$

$\Longrightarrow \sf x=1+i\sqrt{\dfrac{2}{3}}, \quad 1-i\sqrt{\dfrac{2}{3}}$

6 0

2 years ago

Read 2 more answers

X+3/3=y+2/2,then x/3=

Nina [5.8K]

It would equal 3
i hope this helps

4 0

3 years ago

joseph and patrick purchase school supplies in the book store. Joseph purchases four notebooks and three pens for $10.65. Patric

natali 33 [55]

I think it is going to be 3.55 for each notebook and 1.9 for each pen

6 0

3 years ago

Nico is trying to divide a 6 by 4 inches of rectangular cartoon sheet into pieces of squares. Given that he used up all of the m

ELEN [110]

Answer:

Minimum of 6 squares.

Step-by-step explanation:

The dimension of the rectangular carton = 6 by 4 inches.

The area of the carton = length x width

= 6 x 4

= 24 square inches

Assume that we have a square of side length 2 inches, then;

area of the square = length x length

= 2 x 2

= 4 square inches

So that since all materials is to be used,

the minimum number of squares that it can produce = $\frac{24}{4}$

= 6

6 0

3 years ago

PLS HELP ASAP WILL GIVE BRAINLEAST

MrMuchimi

Answer:

it should be (-6,-2) if I remember how to do this correctly

7 0

3 years ago