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2 years ago

Okay Guys plz plz help like really

Mathematics

1 answer:

RSB [31]2 years ago

3 0

Answer:

Step-by-step explanation:

Plug in the value of k into your expression and solve.

40-4k^3

40-4(2)^3

40-4(8)

40-32

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Scilla [17]

Take the cross product, then normalize the result.

$\mathbf a\times\mathbf b=\begin{vmatrix}\mathbf i&\mathbf j&\mathbf k\\1&7&1\\1&11&1\end{vmatrix}=-4\,\mathbf i+4\,\mathbf k$

This has norm

$\|\mathbf a\times\mathbf b\|=\sqrt{(-4)^2+4^2}=4\sqrt2$

and so a unit vector orthogonal to both given vectors is

$\dfrac{\mathbf a\times\mathbf b}{\|\mathbf a\times\mathbf b\|}=-\dfrac1{\sqrt2}\,\mathbf i+\dfrac1{\sqrt2}\,\mathbf k$

An equally correct answer would be the negative of this vector, since $\mathbf b\times\mathbf a=-\mathbf a\times\mathbf b$ .

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3 years ago

Solve the equation by completing the square and then solving for x. 1. x^2-6x=12 2. 2x^2-24x=-20

Paraphin [41]

Answer: (x - 3)² = 21

Step-by-step explanation:

x² - 6x + ____ = 12 + ____

↓ ↑ ↑

$\frac{-6}{2} = (-3)^{2}$

x² - 6x + 9 = 12 + 9

(x - 3)² = 21

*******************************************************

Answer: (x - 6)² = 26

Step-by-step explanation:

2x² - 24x = -20

÷2 ÷2 ÷2

x² - 12x = -10

x² - 12x + ____ = -10 + ____

↓ ↑ ↑

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x² - 12x + 36 = -10 + 36

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To Find :

How many gallons of a 80% antifreeze solution must be mixed with 100 gallons of 20% antifreeze to get a mixture that is 70% antifreeze.

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A= 3.14x15 squared

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