!!!!!!!HELP ASAP!!!!!!!!!

The percentage 21 is of 28 is equal to the percentage 30 is of 40<br> True?<br> or false?

katovenus [111]

Answer:

False

Step-by-step explanation:

75%

21

28 5.88

21 x 28

100

= 5.88

x 100% = 75%33.3333333333%

28 - 21

21

x 100% = 33.3333333333%

5 0

2 years ago

Find the exact value of the trigonometric expression given that sin u = − 8 17 and cos v = − 24 25 . (Both u and v are in Quadra

Rashid [163]

Answer: sin u = -5/13 and cos v = -15/17

Step-by-step explanation:

The nice thing about trig, a little information goes a long way. That’s because there is a lot of geometry and structure in the subject. If I have sin u = opp/hyp, then I know opp is the opposite side from u, and the hypotenuse is hyp, and the adjacent side must fit the Pythagorean equation opp^2 + adj^2 = hyp^2.

So for u: (-5)^2 + adj^2 = 13^2, so with what you gave us (Quad 3),

==> adj of u = -12 therefore cos u = -12/13

Same argument for v: adj = -15,

opp^2 + (-15)^2 = 17^2 ==> opp = -8 therefore sin v = -8/17

The cosine rule for cos (u + v) = (cos u)(cos v) - (sin u)(sin v) and now we substitute: cos (u + v) = (-12/13)(-15/17) - (-5/13)(-8/17)

I am too lazy to do the remaining arithmetic, but I think we have created a way to approach all of the similar problems.

3 0

2 years ago

skew-symmetric 3 x 3 matrices form as subspace of all 3 x 3 matrices and find a basis for this subspace.

Neporo4naja [7]

Answer:

a) ∝A ∈ W

so by subspace, W is subspace of 3 × 3 matrix

b) therefore Basis of W is

={ ${\left[\begin{array}{ccc}0&1&0\\-1&0&0\\0&0&0\end{array}\right]$ $,\left[\begin{array}{ccc}0&0&1\\0&0&0\\-1&0&0\end{array}\right]$ $,\left[\begin{array}{ccc}0&0&0\\0&0&1\\0&-1&0\end{array}\right]$ }

Step-by-step explanation:

Given the data in the question;

W = { A| Air Skew symmetric matrix}

= {A | A = -A^T }

A ; O⁻ = -O⁻^T O⁻ : Zero mstrix

O⁻ ∈ W

now let A, B ∈ W

A = -A^T B = -B^T

(A+B)^T = A^T + B^T

= -A - B

- ( A + B )

⇒ A + B = -( A + B)^T

∴ A + B ∈ W.

∝ ∈ | R

(∝.A)^T = ∝A^T

= ∝( -A)

= -( ∝A)

(∝A) = -( ∝A)^T

∴ ∝A ∈ W

so by subspace, W is subspace of 3 × 3 matrix

A ∈ W

A = -AT

A = $\left[\begin{array}{ccc}o&a&b\\-a&o&c\\-b&-c&0\end{array}\right]$

= $a\left[\begin{array}{ccc}0&1&0\\-1&0&0\\0&0&0\end{array}\right]$ $+b\left[\begin{array}{ccc}0&0&1\\0&0&0\\-1&0&0\end{array}\right]$ $+c\left[\begin{array}{ccc}0&0&0\\0&0&1\\0&-1&0\end{array}\right]$

therefore Basis of W is

={ ${\left[\begin{array}{ccc}0&1&0\\-1&0&0\\0&0&0\end{array}\right]$ $,\left[\begin{array}{ccc}0&0&1\\0&0&0\\-1&0&0\end{array}\right]$ $,\left[\begin{array}{ccc}0&0&0\\0&0&1\\0&-1&0\end{array}\right]$ }

8 0

3 years ago

HELP ITS TIMEDDD !!!!

lidiya [134]

Answer:

SAS.........,..,....

8 0

3 years ago

Which expression represents the

ki77a [65]

The expression that represents the number of reams of paper produced in the second year is 4.704 x $10^{10}$ (option d)

<h3>What is the expression that represents the reams produced in the second year. </h3>

The quantity of paper produced in the first year is written in scientific notation. Scientific notation is used to compress larger numbers into smaller numbers.

In order to write a number in scientific notation, the number is written as a decimal number, between 1 and 10 and multiplied by a power of 10.

For example, The number 5 x 10³ is equivalent to 500

Paper produced in the second year = paper produced in the first year x 5.6

(8.4 x $10^{9}$ ) x 5.6 = 47.04 x $10^{9}$

4.704 x $10^{9 + 1}$

= 4.704 x $10^{10}$

To learn more about scientific notation, please check: brainly.com/question/25334755

#SPJ1

5 0

2 years ago