All categories

2 years ago

Which is true. A B C D

Mathematics

2 answers:

Talja [164]2 years ago

8 0

The answer is B
It should be correct

gtnhenbr [62]2 years ago

7 0

Answer:

Step-by-step explanation:

You might be interested in

Is matrix multiplication comutative?

konstantin123 [22]

Answer:

Matrix multiplication is not conmutative

Step-by-step explanation:

The matrix multiplication can be performed if the number of columns of the first matrix is equal to the number of rows of the second matrix

Let A with dimension mxn and B with dimension nxp represent two matrix

The multiplication of A by B is a matrix C with dimension mxp, but the multiplication of B by A is can't be calculated because the number of columns of B is not the number of rows of A. Therefore, you can notice that is not conmutative in general.

But even if the multiplication of AB and BA is defined (For example if A and B are squared matrix of 2x2) the multiplication is not necessary conmutative.

The matrix multiplication result is a matrix which entries are given by dot product of the corresponding row of the first matrix and the corresponding column of the second matrix:

$A=\left[\begin{array}{ccc}a11&a12\\a21&a22\end{array}\right]\\B= \left[\begin{array}{ccc}b11&b12\\b21&b22\end{array}\right]\\AB = \left[\begin{array}{ccc}a11b11+a12b21&a11b12+a12b22\\a21b11+a22b21&a21b12+a22b22\end{array}\right]\\\\BA=\left[\begin{array}{ccc}b11a11+b12a21&b11a12+b12a22\\b21a11+b22ba21&b21a12+b22a22\end{array}\right]$

Notice that in general, the result is not the same. It could be the same for very specific values of the elements of each matrix.

6 0

2 years ago

Use spherical coordinates. evaluate (9 − x2 − y2) dv, where h is the solid hemisphere x2 + y2 + z2 ≤ 4, z ≥ 0.

avanturin [10]

In spherical coordinates, we have

$\begin{cases}x=\rho\cos\theta\sin\varphi\\y=\rho\sin\theta\sin\varphi\\z=\rho\cos\varphi\end{cases}$

which gives volume element

$\mathrm dV=\mathrm dx\,\mathrm dy\,\mathrm dz=\rho^2\sin\varphi\,\mathrm d\rho\,\mathrm d\varphi\,\mathrm d\theta$

and so the triple integral is given by

$\displaystyle\iiint_H(9-x^2-y^2)\,\mathrm dV$
$=\displaystyle\int_{\theta=0}^{\theta=2\pi}\int_{\varphi=0}^{\varphi=\pi/2}\int_{\rho=0}^{\rho=2}(9-\rho^2\sin^2\varphi)\rho^2\sin\varphi\,\mathrm d\rho\,\mathrm d\varphi\,\mathrm d\theta$
$=\displaystyle2\pi\int_{\varphi=0}^{\varphi=\pi/2}\int_{\rho=0}^{\rho=2}(9\rho^2\sin\varphi-\rho^4\sin^3\varphi)\,\mathrm d\rho\,\mathrm d\varphi$
$=\dfrac{592\pi}{15}$

4 0

2 years ago

I need help on this question plz answer me

ahrayia [7]

A stem and leaf plot (histogram) shows the mode as the longest list of "leaves." It is the easiest to use for finding mode.

A box-and-whisker plot tells you nothing about relative frequencies.

A scatter plot or line graph would require careful re-interpretation to determine the mode. If the amount of data is large and there are many data values with about the same high frequency, these charts may be unhelpful, too.

8 0

3 years ago

In the equation m = k + 3, m is the:

Lorico [155]

Answer:

Step-by-step explanation:

m is the dependent variable; it represents the value of a linear function of k:

m = f(k) = k + 3

6 0

2 years ago

Dave took an exam with 40 questions. He answered 26 correctly. What was his grade for the exam? Write the grade as a percent .

andrey2020 [161]

Answer:

65%

Step-by-step explanation:

26/40 = .65

Multiply by 100 to get the percent

4 0

2 years ago

Read 2 more answers