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3 years ago

What calculation can be used to find the value of p in the equation p^3 =8

Mathematics

1 answer:

blsea [12.9K]3 years ago

6 0

Cube Root

${p}^{3} = 8 \\ p = \sqrt[3]{8} \\ p = \sqrt[3]{ 2\times 2 \times 2} \\ p = 2$

Formula

${p}^{3} - 8 = 0$

Use the following formula.

${x}^{3} - {y}^{3} = (x - y)( {x}^{2} + xy + {y}^{2} )$

$(p - 2)( {p}^{2} + 2p + 4)$

The expression p²+2p+4 has the discriminant less than 0 ( D < 0 ).

Thus, remove the expression and leave only p-2

$p - 2 = 0 \\ p = 2$

Substitution

The most obvious number that multiplies itself three times and equal 8 is 2.

Substitute p = 2

${p}^{3} = 8 \\ {2}^{3} = 8 \\ 2 \times 2 \times 2 = 8 \\ 8 = 8$

The equation is true, thus 2 is the answer.

You might be interested in

Use the definition of Taylor series to find the Taylor series, centered at c, for the function. f(x) = sin x, c = 3π/4

anyanavicka [17]

Answer:

$\sin(x) = \sum\limit^{\infty}_{n = 0} \frac{1}{\sqrt 2}\frac{(-1)^{n(n+1)/2}}{n!}(x - \frac{3\pi}{4})^n$

Step-by-step explanation:

Given

$f(x) = \sin x\\$

$c = \frac{3\pi}{4}$

Required

Find the Taylor series

The Taylor series of a function is defines as:

$f(x) = f(c) + f'(c)(x -c) + \frac{f"(c)}{2!}(x-c)^2 + \frac{f"'(c)}{3!}(x-c)^3 + ........ + \frac{f*n(c)}{n!}(x-c)^n$

We have:

$c = \frac{3\pi}{4}$

$f(x) = \sin x\\$

$f(c) = \sin(c)$

$f(c) = \sin(\frac{3\pi}{4})$

This gives:

$f(c) = \frac{1}{\sqrt 2}$

We have:

$f(c) = \sin(\frac{3\pi}{4})$

Differentiate

$f'(c) = \cos(\frac{3\pi}{4})$

This gives:

$f'(c) = -\frac{1}{\sqrt 2}$

We have:

$f'(c) = \cos(\frac{3\pi}{4})$

Differentiate

$f"(c) = -\sin(\frac{3\pi}{4})$

This gives:

$f"(c) = -\frac{1}{\sqrt 2}$

We have:

$f"(c) = -\sin(\frac{3\pi}{4})$

Differentiate

$f"'(c) = -\cos(\frac{3\pi}{4})$

This gives:

$f"'(c) = - * -\frac{1}{\sqrt 2}$

$f"'(c) = \frac{1}{\sqrt 2}$

So, we have:

$f(c) = \frac{1}{\sqrt 2}$

$f'(c) = -\frac{1}{\sqrt 2}$

$f"(c) = -\frac{1}{\sqrt 2}$

$f"'(c) = \frac{1}{\sqrt 2}$

$f(x) = f(c) + f'(c)(x -c) + \frac{f"(c)}{2!}(x-c)^2 + \frac{f"'(c)}{3!}(x-c)^3 + ........ + \frac{f*n(c)}{n!}(x-c)^n$

becomes

$f(x) = \frac{1}{\sqrt 2} - \frac{1}{\sqrt 2}(x - \frac{3\pi}{4}) -\frac{1/\sqrt 2}{2!}(x - \frac{3\pi}{4})^2 +\frac{1/\sqrt 2}{3!}(x - \frac{3\pi}{4})^3 + ... +\frac{f^n(c)}{n!}(x - \frac{3\pi}{4})^n$

Rewrite as:

$f(x) = \frac{1}{\sqrt 2} + \frac{(-1)}{\sqrt 2}(x - \frac{3\pi}{4}) +\frac{(-1)/\sqrt 2}{2!}(x - \frac{3\pi}{4})^2 +\frac{(-1)^2/\sqrt 2}{3!}(x - \frac{3\pi}{4})^3 + ... +\frac{f^n(c)}{n!}(x - \frac{3\pi}{4})^n$

Generally, the expression becomes

$f(x) = \sum\limit^{\infty}_{n = 0} \frac{1}{\sqrt 2}\frac{(-1)^{n(n+1)/2}}{n!}(x - \frac{3\pi}{4})^n$

Hence:

$\sin(x) = \sum\limit^{\infty}_{n = 0} \frac{1}{\sqrt 2}\frac{(-1)^{n(n+1)/2}}{n!}(x - \frac{3\pi}{4})^n$

3 0

2 years ago

A rectangular garden has an area of 22 square feet. If its length is 7 feet less than twice its width, find the dimensions of t

DedPeter [7]

Answer: Width is 5.5 ft, length is 18 ft

7 0

2 years ago

Please answer if you know the solution. Thx

LenKa [72]

Answer:

the first blank is 10

and the second blank is 5

Step-by-step explanation:

5 0

3 years ago

Help please!

larisa86 [58]

Answer:

The point at (-7, -5) = a

The point at (9, 3) = b

The point at (-3, 7) = c

The "a" point of the triangle is 12 units away from the center point.

So, 12 x 1/4

=> 12/4

=> 3

So, the "a" point of the dilated figure is 3 units left from the center.

=> So, the dilated "a" point is at (2, -5)

The "b" point is 8/4 (= rise/run = y-axis / x-axis) from the center point.

=> 8/4 = 2

So, the "b" point of the dilated figure is 1 unit right and 2 units up from the center point.

=> So, the dilated "b" point is at (6, -3)

The "c" point is 12/8 units away from the center point.

=> 12/8 x 1/4

=> 3/2

So, the "c" point of the dilated figure is 3 units up and 2 units left from the center point.

=> So, the dilated "c" point is at (3, -2)

7 0

2 years ago

You were paid $82.50 for seven 1/2 hours of work what is your rate of pay

sertanlavr [38]

$11 per hour. Divide 82.5 by 7.5 and you get how much money she earns in an hour (11 dollars)

6 0

3 years ago