Indica las expresiones que determinan conjuntos. Explica tu respuesta

Tcecarenko [31]

$c^2$ $2c^2 + 13c +21 \\4c^2 + 13(2)c + 42\\(2c + 6)(2c+7)\\(c+3)(2c+7)$

This is a way to factoring trinomials (there exist different equivalent methods).

Multiply the trinomial but the term accompanying $c^2$ . This is the second line. Then, you could take the square of the $4c^2$ , ant try to create a factor () () that will correspond to the expression in the second line. That is, we want $4c^2 + 13(2) c + 42 = (2c + ?) (2c + ?)$

In ? we put the corresponding numbers that, if we multiply them we will obtain 42, and if we add them we will obtain 13. This numbers are 6 and 7. Then, we have $(2c + 6) (2c +7)$

The last step is divide by the number that we multipy in the first step.

4 0

3 years ago

One of two complementary angles measures 30 degrees more than three times the other. Find each angle.

Leviafan [203]

The two complementary angles are:

95° and 15°

Step-by-step explanation:

Let x be one angle

then the other angle will be 90-x

As the sum of complementary angles is 90

So,

then according to statement

$x = 3(90-x)+30\\x = 270-3x +30\\x = 300-3x\\x+3x = 300\\4x = 300\\x = \frac{300}[4}\\x = 75\\and\\90 -x = 90 - 75 = 15$

The two complementary angles are:

95° and 15°

Keywords: Angles, triangles

Learn more about angles at:

#LearnwithBrainly

7 0

3 years ago

What is the Point slope equation

anastassius [24]

Answer:

y - y1 = m(x - x1)

Step-by-step explanation:

The point slope form equation is [ y - y1 = m(x - x1) ]

(x1, y1) is any given point on the line.

m is the slope.

To solve this you would need these things:

Slope (y2-y1/x2-x1)
Y-intercept (y = mx + b)

Best of Luck!

3 0

3 years ago

the volume v of a right circular cylinder of radius r and heigh h is V = pi r^2 h 1. how is dV/dt related to dr/dt if h is const

laiz [17]

In general, the volume

$V=\pi r^2h$

has total derivative

$\dfrac{\mathrm dV}{\mathrm dt}=\pi\left(2rh\dfrac{\mathrm dr}{\mathrm dt}+r^2\dfrac{\mathrm dh}{\mathrm dt}\right)$

If the cylinder's height is kept constant, then $\dfrac{\mathrm dh}{\mathrm dt}=0$ and we have

$\dfrac{\mathrm dV}{\mathrm dt}=2\pi rh\dfrac{\mathrm dt}{\mathrm dt}$

which is to say, $\dfrac{\mathrm dV}{\mathrm dt}$ and $\dfrac{\mathrm dr}{\mathrm dt}$ are directly proportional by a factor equivalent to the lateral surface area of the cylinder ( $2\pi r h$ ).

Meanwhile, if the cylinder's radius is kept fixed, then

$\dfrac{\mathrm dV}{\mathrm dt}=\pi r^2\dfrac{\mathrm dh}{\mathrm dt}$

since $\dfrac{\mathrm dr}{\mathrm dt}=0$ . In other words, $\dfrac{\mathrm dV}{\mathrm dt}$ and $\dfrac{\mathrm dh}{\mathrm dt}$ are directly proportional by a factor of the surface area of the cylinder's circular face ( $\pi r^2$ ).

Finally, the general case ( $r$ and $h$ not constant), you can see from the total derivative that $\dfrac{\mathrm dV}{\mathrm dt}$ is affected by both $\dfrac{\mathrm dh}{\mathrm dt}$ and $\dfrac{\mathrm dr}{\mathrm dt}$ in combination.

8 0

2 years ago

At 1:00, the minute and hour hands form a 30º angle. What is the measure of the angle at 8:00, in degrees?

Anvisha [2.4K]

The angle would be obtuse. So it would be over a 90* angle.
•1= 30*
•2= 60*
•3=90*
•4=120*
•5=150*
•6=180*
•7=210
•8=230*

3 0

2 years ago