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3 years ago

Compute the value of the discriminant and give the number of real solutions of the quadratic equation. -2x^2+8x-1=0

1 answer:

4 0

Divide given eq. by -2, we get, x^2-4x+0.5=0. Here a=1, b=-4 and c=0.5. As disccriminant is given by sqrt(b^2-4*a*c).so sqrt((-4)^2-4*1*0.5)=3.7417.
Real roots are x1,2=-b+-discriminant
x1=-4+3.7417=-0.2583 and x2=-4-3.7417=-7.7417

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What coordinates on the unit circle are associated with the angle measure?

Varvara68 [4.7K]

The tangent of the given angles are the ratios y to the x coordinate of

the point of the terminal side on the unit circle.

The correct options are;

$\dfrac{34 \cdot \pi}{3} \Longleftrightarrow \underline{ \left(-\dfrac{1}{2}, \ -\dfrac{\sqrt{3} }{2} \right)}$

$-\dfrac{7 \cdot \pi}{4} \Longleftrightarrow \underline{ \left(\dfrac{\sqrt{2} }{2}, \ \dfrac{\sqrt{2} }{2} \right)}$

$210^{\circ} \Longleftrightarrow \underline{ \left(-\dfrac{\sqrt{3} }{2}, \ -\dfrac{1}{2} \right)}$

<h3>How to find the points on the unit circle</h3>

The tangent of an angle is given as follows;

$tan (\theta) = \mathbf{ \dfrac{Opposite}{Adjacent}} = \dfrac{\Delta y}{\Delta x}$

First angle

An angle given is; $\mathbf{\dfrac{34 \cdot \pi}{3}}$

Therefore;

$tan \left(\dfrac{34 \cdot \pi }{3} \right) = \mathbf{ \sqrt{3}}$

The above result can be obtained as follows;

$\sqrt{3} = \mathbf{ \dfrac{-\dfrac{\sqrt{3} }{2} }{-\dfrac{1}{2} }}$

Which is obtained when we have;

$\left( \Delta x, \, \Delta y\right) = \mathbf{\left(-\dfrac{1}{2}, \, -\dfrac{\sqrt{3} }{2} \right)}$

Therefore

The required coordinates is therefore;

$\dfrac{34 \cdot \pi}{3} \Longleftrightarrow \left(-\dfrac{1}{2} , \ -\dfrac{\sqrt{3} }{2} \right)$

Second angle

The angle, $\mathbf{-\dfrac{7 \cdot \pi}{4}}$ , gives; $tan \left(-\dfrac{7 \cdot \pi}{4} \right) = 1$

The above value can be obtained as follows;

$\mathbf{\dfrac{\dfrac{\sqrt{2} }{2} }{\dfrac{\sqrt{2} }{2} }} = 1$

Which gives;

$-\dfrac{7 \cdot \pi}{4} \Longleftrightarrow \left(\dfrac{\sqrt{2} }{2}, \, \dfrac{\sqrt{2} }{2} \right)$

Third angle

The angle 210° gives; tan(210°) = $\mathbf{\frac{1}{\sqrt{3} }}$ , which can be obtained as follows;

$\sqrt{ \dfrac{1}{3} } = \mathbf{\dfrac{-\dfrac{1}{2} }{-\dfrac{\sqrt{3} }{2} }}$

Therefore;

$210^{\circ} \Longleftrightarrow \left(-\dfrac{\sqrt{3} }{2}, \ -\dfrac{1}{2} \right)$

Learn more about the unit circle here:

brainly.com/question/1673530

6 0

2 years ago

Which line is a linear model for the line? 1. A 2. B 3. C 4. D

Rudiy27

2 is the answer i beileve

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$\left\{\begin{array}{ccc}a_1=12\\a_n=a_{n-1}-4\end{array}\right$

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3 years ago

A machine produces open boxes using square sheets of metal. The machine cuts equal-sized squares measuring 2 inches on a side f

docker41 [41]

Answer:

width 9'' length 9''

Step-by-step explanation:

2 " is cut off from both sides

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side = x

height =2

2x^2=162

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3 years ago

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5. Enter the number of pound equal to 448 ounces. 16 ounces = 1 pound

lara31 [8.8K]

Answer:

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Step-by-step explanation:

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