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3 years ago

14

If n is prime number then 2n-1 is prime also?

1 answer:

BlackZzzverrR [31]3 years ago

5 0

Answer:

Step-by-step explanation:

Prime numbers are number that can only be divided by itself and 1.

E.g 2,3,5,7,11,13,17,19,23,29 etc.

So, note that this sequence doesn't have a pattern, it is neither Geometry Progression nor Arithmetic Progression.

Now, let take look at the model given

If n is prime, then 2n-1 is prime

Let take 5 for

n=5 is a prime number

2n-1=2(5)-1=10-1=9

9 is not a prime number so the model doesn't work

A prime number doesn't have sequence so, it cannot be model with sequence.

I hope this help

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2x³+16y³= 2(x³+8y³)

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3 years ago

The function f(x)=(x-1)^2-4 is not one-to-one. If you restrict the domain for f(x) to x(less than or equal to symbol)1, what is

olasank [31]

$\text{We have been given the function }\\
f(x)=(x-1)^2-4\\
\text{Let f(x)=y}\\
y=(x-1)^2-4\\
\text{Swap x and y, we get}\\
\\
x=(y-1)^2-4\\
\text{Now we solve for y}\\
(y-1)^2=x+4\\
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y-1=\pm \sqrt{x+4}\\
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3 years ago

Read 2 more answers

5 less than a number is equivalent to 1 more than three times the number. the number is

lutik1710 [3]

Answer:

x = -1

Step-by-step explanation:

5 less than a number is equivalent to 1 more than three times the number

number = x

x - 5 = 3x + 1

now im going to get the numbers and variable on different sides

x - 5 + 5 = x

3x + 1 - 3x = 1

x + 3x = 4x

1 - 5 = -4

4x = -4

lastly im going to divide each side by 4

4x / 4 = x

-4 / 4 = -1

x = -1

3 0

3 years ago

PLZZ HELLO ILL GIVE BRAINLIST

sp2606 [1]

Answer:

X= 1

Step-by-step explanation:

2, + the 2 her brother gives her is too high, its 4.

which means we go lower.

0 can't be right, because 0 + 2 = 2, not 3.

lets try 1.

1 + 2 = 3.

So that means X = 3.

3 0

3 years ago

Graph the data in the table. Which kind of function best models the data? Write an equation to model the data. quadratic; y = 2.

Oksanka [162]

Answer:

Option (1)

Step-by-step explanation:

x -2 -1 0 1 2

y 10 2.5 0 2.5 3.0

Ist difference,

$d_1=y_2-y_1$

$=2.5-10=-7.5$

$d_2=y_3-y_2$

$=0-2.5$

= -2.5

$d_3=y_4-y_3$

$=2.5-0$

= 2.5

$d_4=y_5-y_4$

$=10.0-2.5$

= 7.5

2nd difference,

$x_1=d_2-d_1$

$=-2.5+7.5$

= 5

$x_2=d_3-d_2$

$=2.5+2.5$

= 5

$x_3=d_4-d_3$

$=7.5-2.5$

= 5

Since 2nd difference is common, given table represents a quadratic equation.

Let the equation is,

y = ax²+ bx + c

For a point (0, 0) passing through the quadratic equation,

0 = c

Therefore, quadratic equation is y = ax² + bx

Since ordered pair (-1, 2.5) passes through the graph of the function,

2.5 = a(-1)² + b(-1)

a - b = 2.5 ------(1)

For another point (1, 2.5)

2.5 = a(1)² + b(1)

a + b = 2.5 ------(2)

By adding equations (1) and (2),

2a = 5

a = 2.5

and from equation (2)→ y = 0

Therefore, equation of the quadratic function given in the table is y = 2.5x²

Option (1) is the answer.

8 0

3 years ago