Find the cosine of angle A to the nearest 100th.

Given:

The matrix is:

[tex]A=\begin{bmatrix}\cos x&-\sin x\\\sin x&\cos x\end{bmatrix}[/tex]

To show:

[tex](A^{-1})^{-1}=A[/tex]

Solution:

If a matrix is:

[tex]M=\begin{bmatrix}a&b\\c&d\end{bmatrix}[/tex]

Then,

[tex]M^{-1}=\dfrac{1}{ad-bc}\begin{bmatrix}d&-b\\-c&a\end{bmatrix}[/tex]

We have,

[tex]A=\begin{bmatrix}\cos x&-\sin x\\\sin x&\cos x\end{bmatrix}[/tex]

Using the above formula, we get

[tex]A^{-1}=\dfrac{1}{(\cos x)(\cos x)-(-\sin x)(\sin x)}\begin{bmatrix}\cos x&\sin x\\-\sin x&\cos x\end{bmatrix}[/tex]

[tex]A^{-1}=\dfrac{1}{\cos^2x+\sin^2x}\begin{bmatrix}\cos x&\sin x\\-\sin x&\cos x\end{bmatrix}[/tex]

[tex]A^{-1}=\dfrac{1}{1}\begin{bmatrix}\cos x&\sin x\\-\sin x&\cos x\end{bmatrix}[/tex]

[tex]A^{-1}=\begin{bmatrix}\cos x&\sin x\\-\sin x&\cos x\end{bmatrix}[/tex]

Now, the inverse of [tex]A^{-1}[/tex] is:

[tex](A^{-1})^{-1}=\dfrac{1}{(\cos x)(\cos x)-(\sin x)(-\sin x)}\begin{bmatrix}\cos x&-\sin x\\\sin x&\cos x\end{bmatrix}[/tex]

[tex](A^{-1})^{-1}=\dfrac{1}{\cos^2x+\sin^2x}\begin{bmatrix}\cos x&-\sin x\\\sin x&\cos x\end{bmatrix}[/tex]

[tex](A^{-1})^{-1}=\dfrac{1}{1}A[/tex]

[tex](A^{-1})^{-1}=A[/tex]

Hence proved.

Answer:

4. D.

5. C.

6. A.

Step-by-step explanation:

It's just simple ratios... It's been a while since I learned it so I don't really remember how to explain the answers.

Answer:

The ball will reach the same height of 10 meters after 100 meters.

Part A)

100 meters.

Part B)

10 meters.

Step-by-step explanation:

The golf-ball hit by the Seven-Iron is modeled by the equation:

[tex]h=-0.002d^2+0.3d[/tex]

And the ball hit by the Nine-Iron is modeled by the equation:

[tex]h=-0.004d^2+0.5d[/tex]

Where h is the height of the ball after d meters.

When they are at the same height, the two equations will equal each other.

Graphically, this is where the two graphs will intersect.

To solve this using a Ti-84, you can follow these steps (I'm using the Ti-84 Plus Silver Edition):

1) Using [Y=], write and then [GRAPH] the two equations.

2) Press [ZOOM] and [ZOOM OUT] until you can see both graphs clearly.

3) To find the intersection point, press [2ND] and then [CALC] (above [TRACE]).

4) Choose [5) Intersect].

5) Using the arrow keys, click on one graph to choose it as your first curve and the other to choose it as your second curve. (In this case, it doesn't matter which one is which.)

6) When it asks you to guess, put the cursor to as close to the intersection point as possible. Ignore the intersection at the origin point.

7) Press [ENTER], and it should give you your solution.

Therefore, the intersection point (not counting (0,0)) is at (100, 10).

Therefore, the ball will reach the same height of 10 meters after 100 meters.

Answer:

2850

Step-by-step explanation:

1+2+3+4+5+6+7...74+75

just add up all the numbers from 1 to 75

Hello,

The first transform E1 is the homothetie of center (0,0) and ratio=2

The second transform E2 is the homothetie of center (0,0) and ratio=3/2

P=(3,k)

P'=E1(P)= E1((3,k))=(2*3,2*k)=(6,2k)

P''=E2(P')=E2(6,2k)=(3/2*6,3/2*2*k)=(9,3k)=(9,12)

==> 3k=12

k=4

Answer:

I hope the pic i gave is helpful!!!

Answer:

(a) is 8 x 7 x 3 = 168

(b) is 8 x 7 = 56

(b2) is weird I don't know what it's asking

Answer:

FOR LETTER A

Volume of prism (expression) = Length x Width/Breadth x Height

Volume of prism (expression) = 8 units x 7 units x 3 units = 168 cubic units

FOR LETTER B

Area of the shaded base = 8 x 7 = 56 square units

Volume of prism = Area of the shaded base x Height

Volume of prism = 56 square units x 3 units = 168 cubic units

Step-by-step explanation:

To find the volume of rectangular prism, we multiply the length of the prism by the width of the prism by the height of the prism.

Volume of rectangular prism = length × width × height

To get the area of the shaded base, when the base is in rectangular shape:

Definition: Area of rectangle is the region occupied by a rectangle within it's four sides or boundaries.

The area of a rectangle depends on its sides. Basically, the formula for area is equal to the product of length and breadth of the rectangle. Whereas when we speak about the perimeter of a rectangle, it is equal to the sum of all its four sides. Hence, we can say, the region enclosed by the perimeter of the rectangle is its area. But in the case of a square, since all the sides are equal, therefore, the area of the square will be equal to the square of side-length.

Area of rectangle = Length × Breadth

A = l × b

Answer:

300 seconds

Step-by-step explanation:

The first dog run at v₁ = 15 m/sec     the second one run at  v₂ = 12 m/sec

we know that  d = v*t  then  t  =  d/v

Then the first dog will take  300/ 12  =  25 seconds to make a turn

The second will take   300 / 15   =   20 seconds to make a turn

Then the first dog in 12 turns 12*25 will be at the start point, and so will the second one at the turn 15.

To check  first dog    12 *  25 = 300

And the second dog 15 * 20 = 300

That means that time required for the two dogs to be at the start point together is

300 seconds, in that time the first dog finished the 12 turns, and the second had ended the 15.

Another procedure to solve this problem is as follows:

between  12  m/sec and  15 m/sec   the minimum common multiple  is 300 ( 300 is the smaller number that accept 12 and 15 as factors         12*15 = 300) Then when time arrives at 300 seconds the two dogs will be again in the starting point

Answer:

x = 70     y = 140

Step-by-step explanation:

Apologies if I get any names of vocabulary terms wrong, I never pay much attention to the names.

The central angle measure of an arc is the same as the arc's measure. In this case, y is the central angle and 140 is the arc's measure, so y = 140.

The inscribed angle measure of an arc is 1/2 the arc's measure. An inscribed angle lies on the circle. So 140/2 = 70 = x.

Answer:

0.5miles

Step-by-step explanation:

800meters is 0.497097miles

Round 0.497097miles to the nearest hundredth which would be 0.5 miles.

Answer:

Pythagoras theorem states that c²=a²+b²

14²=12²+x²

14²-12²=x²

196-144=x²

52=x²

√52=√x²

7.2111025509279785=x

rounded up to the nearest hundredth=7.21

Answer:

I’m sorry but you need to edit this question, it is incomplete.

Step-by-step explanation:

I see nothing, if there is supposed to be an image attached, please i attach it again, tnx!

I could help you though

Answer:

9a. GCF: 16. LCM: 960

9b. GCF: 55. LCM: 275

9c. GCF: 24. LCM: 114

9d. GCF: 40. LCM: 600

10a. GCF: 120. LCM: 1440

10b. 10, 2, 5, 20

10c. 2880, 4320, 5760, 7200

Answer:

last option

Step-by-step explanation:

3.9x3 -4.1x2+7.3

Hello,

Let's x² the square number

and 3*y the multiple of 3.

[tex]x^2+3y=90\\\\\boxed{y=-\dfrac{1}{3} x^2+30}\\\\[/tex]

2 solutions : for (x,y) as integers : (-6,18) and (6,18)

but one solution for (x²,3y) as integers : (36,54)

Slope intercept form of a line is, y = mx + c where m is the slope and c is constant.

Judging the given equation y = 2x + 5

Slope (m) of the line is 2,

y-intercept of the line,

y = 2x + 5

y = 2×0 + 5

y = 5

Answered by GAUTHMATH

Answer:

m = 2

y intercept = 5

Step-by-step explanation:

The given equation of the line is ,

[tex]\implies y = 2x +5[/tex]

We know that the Standard equation of Slope Intercept Form of the line is,

[tex]\implies y = mx + c[/tex]

Where ,

On comparing to the Standard form of the line we get ,

[tex]\implies Slope = 2 [/tex]

[tex]\implies y - intercept= 5[/tex]

Answer:

ayan po answer nasa picture po

Step-by-step explanation:

where

x

is the number you are trying to compute the (2/3) rds of

Answer:

y + 5 = 2(x - 4)

Step-by-step explanation:

y + 5 = 2(x - 4)

Answer:

a) 71

b) an = a1 + (n-1)×7

c) the 37th term

Step-by-step explanation:

clearly, an+1 = an + 7

so, any new term is the previous term plus 7.

a1 = 8

and then the sequence goes on. starting with a2 we add 7 every time.

so, for an we added 7 n-1 times to a1. n-1 because for a1 we did not have to add 7.

therefore, the building function of this sequence to calculate the nth term is

an = a1 + (n-1)×7

a10 = a1 + 9×7 = 8 + 63 = 71

and

ax = 260 = a1 + (x-1)×7 = 8 + 7x - 7 = 1 + 7x

259 = 7x

x = 37

=> the 37th term of the sequence is 260

Answer:

Linear functions are

f(x) = 0.45 x - 1

f(x) = 5

f(x) = 4.5 x + 18

Quadratic function is

R(x) = 19x^2

Step-by-step explanation:

The linear function is a function in which the degree of function is 1.

So,

f(x) = 0.45 x - 1

f(x) = 5

f(x) = 4.5 x + 18 are the linear functions.

The quadratic function is a function in which the degree of function is 2.

So,

R(x) = 19 x^2 is a quadratic function.

The exponential function is a function which involves the exponents.

Answer:

pic

Step-by-step explanation:

Answer:

A radical is basically a fractional exponent and is denoted by the radical sign (√). The expression x2 means to multiply x by itself (x × x), but when you see the expression √x, you're looking for a number that, when multiplied by itself, equals x. Similarly, 3√x means a number that, when multiplied by itself twice, equals x, and so on. Just as you can multiply numbers with the same exponent, you can do the same with radicals, as long as the superscripts in front of the radical signs are the same. For example, you can multiply (√x × √x) to get √(x2), which just equals x, and (3√x × 3√x) to get 3√(x2). However, the expression (√x × 3√x) can't be simplified any further.

Answer:

a round figure that has no corners or vertices.

Step-by-step explanation:

Answer:

A circle is a shape consisting of all points in a plane that are at a given distance from a given point, the centre; equivalently it is the curve traced out by a point that moves in a plane so that its distance from a given point is constant. The distance between any point of the circle and the centre is called the radius. This article is about circles in Euclidean geometry, and, in particular, the Euclidean plane, except where otherwise noted.

Step-by-step explanation:

Center of a Circle

The center of a circle is the center point in a circle from which all the distances to the points on the circle are equal. This distance is called the radius of the circle.

Here, point P is the center of the circle.

center of the circle center point

Semicircle:

A semi-circle is half of a circle, formed by cutting a whole circle along a line segment passing through the center of the circle. This line segment is called the diameter of the circle.

Answer:

slope= 1/2

y-intercept= 0,7

Answer:

slope = 1/2 or 0.5, the y-intercept is (0,7)

Step-by-step explanation:

Perpendicular lines have negative reciprocal slopes.

This is just a fancy way of saying flip the fraction and change the sign.

So the slope of line c is 7/2.

Answer:

Step-by-step explanation:

Set the equation and solve for x:

Correct choice is B

Answer:

Step-by-step explanation:

See the picture

It should be self-explanatory

The top part of the angle a is:

The bottom part of the angle a is:

The measure of angle a is:

Firstly, draw a line parallel to UT

Something like in the picture

Now,

a = BNU

Also,

BNU + BNM = 165°

Answer:

the highest common factor of 152 and 266 is 38 and the lowest common multiple is 1064

Answer:

Explanation is in the attachment

hope it is helpful to you

Given:

The statement is "-3 raised to the power 0".

To find:

The value of the given expression.

Solution:

We know that [tex]a[/tex] raised to the power [tex]b[/tex] can be written as [tex]a^b[/tex].

Any non zero number raised to the power 0 is always 1. It means,

[tex]a^0=1[/tex], where [tex]a\neq 0[/tex].

-3 raised to the power 0 [tex]=(-3)^0[/tex]

                                         [tex]=1[/tex]

Therefore, the value of the given statement is 1.

Answer:

x = 12

Step-by-step explanation:

First we need to add x & 1/4x.

Pretend there's a 1 infront of x, so that the equation looks like:

1x + 1/4x = 15

To combine the two terms, we need to get the 1 to have the same denominator as 1/4, so let's multiply 1 (which is the same as 1/1) by 4/4.

You get 4/4! Substitute that into the equation:

4/4x + 1/4x = 15

Now combine the terms:

(4/4x + 1/4x = 5/4x)

5/4x = 15

Finally, multiply both sides by 4/5 to cancel out the 5/4:

x = 15*4/5

x = 60/5

x = 12

Hope it helps (●'◡'●)

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