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3 years ago

Which is the graph of a quadratic equation that has a negative discriminant

Mathematics

2 answers:

sergejj [24]3 years ago

8 0

Answer:

The only one

Step-by-step explanation:

The one that is shown has a negative b^2-4ac value.

We know this because the function has no real roots -> that means that they must be complex, which can only occur if b^2-4ac < 0

tekilochka [14]3 years ago

7 0

Answer:

it's D, the last graph.

Step-by-step explanation:

took the unit test review and made a 100

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A container is filled with water. This container has a small hole. After 20 minutes the amount of water in the container is 600

Grace [21]

Answer:

100 minutes and yes

Step-by-step explanation:

4 0

2 years ago

Determine the formula for the nth term of the sequence:<br>-2,1,7,25,79,...

rodikova [14]

A plausible guess might be that the sequence is formed by a degree-4* polynomial,

$x_n = a n^4 + b n^3 + c n^2 + d n + e$

From the given known values of the sequence, we have

$\begin{cases}a+b+c+d+e = -2 \\ 16 a + 8 b + 4 c + 2 d + e = 1 \\ 81 a + 27 b + 9 c + 3 d + e = 7 \\ 256 a + 64 b + 16 c + 4 d + e = 25 \\ 625 a + 125 b + 25 c + 5 d + e = 79\end{cases}$

Solving the system yields coefficients

$a=\dfrac58, b=-\dfrac{19}4, c=\dfrac{115}8, d = -\dfrac{65}4, e=4$

so that the n-th term in the sequence might be

$\displaystyle x_n = \boxed{\frac{5 n^4}{8}-\frac{19 n^3}{4}+\frac{115 n^2}{8}-\frac{65 n}{4}+4}$

Then the next few terms in the sequence could very well be

$\{-2, 1, 7, 25, 79, 208, 466, 922, 1660, 2779, \ldots\}$

It would be much easier to confirm this had the given sequence provided just one more term...

* Why degree-4? This rests on the assumption that the higher-order forward differences of $\{x_n\}$ eventually form a constant sequence. But we only have enough information to find one term in the sequence of 4th-order differences. Denote the k-th-order forward differences of $\{x_n\}$ by $\Delta^{k}\{x_n\}$ . Then

• 1st-order differences:

$\Delta\{x_n\} = \{1-(-2), 7-1, 25-7, 79-25,\ldots\} = \{3,6,18,54,\ldots\}$

• 2nd-order differences:

$\Delta^2\{x_n\} = \{6-3,18-6,54-18,\ldots\} = \{3,12,36,\ldots\}$

• 3rd-order differences:

$\Delta^3\{x_n\} = \{12-3, 36-12,\ldots\} = \{9,24,\ldots\}$

• 4th-order differences:

$\Delta^4\{x_n\} = \{24-9,\ldots\} = \{15,\ldots\}$

From here I made the assumption that $\Delta^4\{x_n\}$ is the constant sequence {15, 15, 15, …}. This implies $\Delta^3\{x_n\}$ forms an arithmetic/linear sequence, which implies $\Delta^2\{x_n\}$ forms a quadratic sequence, and so on up $\{x_n\}$ forming a quartic sequence. Then we can use the method of undetermined coefficients to find it.

5 0

2 years ago

Is the following function an even function, odd function, or neither?

expeople1 [14]

Answer:

I think neither but i suggest you not take my word for it.

Step-by-step explanation:

3 0

3 years ago

The monthly list of expenditures on your credit card statement can be very helpful at tax time to find items for which you are e

lakkis [162]

Answer: Yes, your monthly list of expenditures on your credit card statement could very helpful at tax time.

When it comes time to file your taxes, there are a variety of different items that could be deductible.

For example, if you operate your own business, you may be able to deduct certain expense. Also, if you have a lot of medical expenses, they could be tax deductible. If you donate money to charitable organizations, it could be tax deductible.

It would be wise to save your statements and look for deductions.

5 0

3 years ago

Find the cost in dollars of the operating a 60-W lamp continuously for 1 week when the power utility rate is 18 cents/kWh .

Alex

<h2>Answer:</h2>

The cost in dollars is:

$ 1.8144

<h2>Step-by-step explanation:</h2>

It is given that:

The 60-W lamp is operated continuously for 1 week.

We know that:

1 week=7 days

and 1 day=24 hours

This means that:

1 week=24×7

i.e. 1 week= 168 hours

Also, 1 kW=1000 W

This means that:

1 W=0.001 kW

Hence,

60-W=0. 060 KW

i.e. Power= 0.60 KW

Hence, the energy consumed is:

Energy=Power×Time

i.e.

Energy=0.060×168

i.e.

Energy=10.08 KWh

Also, cost of 1 KWh=18 cents

We know that:

1 cent=0.01 dollar

This means that:

18 cents=0.18 dollar

i.e.

Cost of 1 KWh=$ 0.18

Hence, cost of 10.08 KWh is: $ (0.18×10.08)

i.e.

Cost of 10.08 KWh is: $ 1.8144

7 0

3 years ago