All categories

4 years ago

Help me please with math

Mathematics

1 answer:

fomenos4 years ago

4 0

Let's make a table of differences

0 3 8 15 24

3 5 7 9

2 2 2

Constant second difference means a quadratic polynomial,

f(n)=an² + bn +c

f(1)=0, f(2)=3, f(3)=8

0 = a+b+c

3 = 4a + 2b + c

8 = 9a + 3b + c

Subtracting pairs

3 = 3a+b

5 = 5a + b

Subtracting,

2 = 2a

a = 1

b = 5 - 5a = 0

c = -a-b = -1

f(n)=n² -1

Duh, shoulda noticed that at the beginning.

f(17)=17²-1 = 288

a₁ =5

aₙ = aₙ₋₁ - 7

aₙ = a₁ + d(n-1)

aₙ = 5 - 7(n-1)

a₇ = 5 - 7(6) = -37

Answer: -37

You might be interested in

Solve system of equations <br><br> 3x+6y=3 <br> X+2y=1

pav-90 [236]

Answer:

has infinite solution

Step-by-step explanation:

(x,y)=(1-2a,a) where a is an element of any real number

7 0

3 years ago

If Olivia makes a smoothie with a ratio 7 strawberries to 2 bananas, how many strawberries would she use with 3 bananas?

Leviafan [203]

Answer:

Step-by-step explanation:

7strawberries 2 bananas 3 and she use the 3 bananas

and answer is.13

5 0

3 years ago

Read 2 more answers

Which of the following functions computes a value such that 2.5% of the area under the standard normal distribution lies in the

fiasKO [112]

Answer:

a) NORM.S.INV(0.975)

Step-by-step explanation:

1) Some definitions

The standard normal distribution is a particular case of the normal distribution. The parameters for this distribution are: the mean is zero and the standard deviation of one. The random variable for this distribution is called Z score or Z value.

NORM.S.INV Excel function "is used to find out or to calculate the inverse normal cumulative distribution for a given probability value"

The function returns the inverse of the standard normal cumulative distribution(a z value). Since uses the normal standard distribution by default the mean is zero and the standard deviation is one.

2) Solution for the problem

Based on this definition and analyzing the question :"Which of the following functions computes a value such that 2.5% of the area under the standard normal distribution lies in the upper tail defined by this value?".

We are looking for a Z value that accumulates 0.975 or 0.975% of the area on the left and by properties since the total area below the curve of any probability distribution is 1, then the area to the right of this value would be 0.025 or 2.5%.

So for this case the correct function to use is: NORM.S.INV(0.975)

And the result after use this function is 1.96. And we can check the answer if we look the picture attached.

6 0

4 years ago

If the following system of equations was written as a matrix equation in the form AX = C, and matrix A was expressed in the form

IrinaVladis [17]

Answer: a-b+c+d =4

Step-by-step explanation:

The given system of equation is

$2x+8y=7\\4x-2y=9$

from this we have the following matrices

$A_1 =\begin{bmatrix}\\2 &8 \\ \\4&2 \\\end{bmatrix}\ ,X=\begin{bmatrix}\\x\\ \\y\\\end{bmatrix}\text{and}\ C=\begin{bmatrix}\\7\\ \\9\\\end{bmatrix}$

the given matrix A = $\begin{bmatrix}\\a &c \\ \\b &d \\\end{bmatrix}$

On comparing Matrix $A_1$ with Matrix A

$\begin{bmatrix}\\a &c \\ \\b &d \\\end{bmatrix}=\begin{bmatrix}\\2&8 \\ \\4 &-2 \\\end{bmatrix}$

we have the following values

a=2 ,b=4,c=8,d=-2

Thus a-b+c+d =2-4+8+(-2)=4

8 0

3 years ago

Read 2 more answers

Find the numerical value of the log expression. \log a=7\hspace{15px} \log b=10\hspace{15px} \log c=3 loga=7logb=10logc=3 \log \

bija089 [108]

Answer:

Step-by-step explanation:

$\log a=7\hspace{15px} \log b=10\hspace{15px} \log c=3\\\\ \log \dfrac{a^8c^2}{b^3}=8\log{a}+2\log{c}-3\log{b}=(8)(7)+(2)(3)-(3)(10)\\\\=56+6-30=\boxed{32}$

The applicable rules of logarithms are ...

log(ab/c) = log(a) +log(b) -log(c)

log(a^b) = b·log(a)

6 0

3 years ago