Prove that cos 3A = cos (2A+A)
cos 3A = 4 cos³A – 3cosA..... Where from the cos A ....does sin A * cos A give cos A??


Cos 3A = cos (2A +A)
Cos 2A cos A - Sin2A sinA
(2cos²A-1)cosA-(2sinA cos A) sinA
2cos³A - cos A - 2 sin²A cos A
2 cos³A-cos A - 2(1-cos²A)cos A
2 cos³A - cos A - 2cos A + 2 cos³A

Cos3A = 4cos³A-3cos A​

Answer:

125a^3 + 300a^2b + 240ab^2 + 64b^3

Step-by-step explanation:

The volume of a cube is the cube of the side length.

V = s^3

Here, the side length of the cube is 5a + 4b, so we cube 5a + 4b.

V = (5a + 4b)^3

V = (5a + 4b)(5a + 4b)(5a + 4b)

V = (25a^2 + 20ab + 20ab + 16b^2)(5a + 4b)

V = (25a^2 + 40ab + 16b^2)(5a + 4b)

V = 125a^3 + 100a^2b + 200a^2b + 160ab^2 + 80ab^2 + 64b^3

V = 125a^3 + 300a^2b + 240ab^2 + 64b^3

Answer:

9

i did this question before

Answer:

The value of x is 9.

Step-by-step explanation:

Given equation,

[tex](x+2)^2=a[/tex]

If x = 1 is the solution of this equation,

Then it will satisfy the equation,

[tex]\implies (1+2)^2=a[/tex]

[tex]\implies (3)^2=a[/tex]

[tex]\implies a = 9[/tex]

Hence, the value of x is 9 if x = 1 is the solution of the given equation.

Answer:  3

Step-by-step explanation:

Median is the middle number if it is an odd number or if it is even you add the two middle numbers and divide by 2

The median cleanliness rating for Restaurant A is 3.

The median of Restaurant A's cleanliness ratings can be found by arranging the ratings in order from lowest to highest and determining the middle value. In this case, the ratings are 1, 2, 3, 4, and 5. Since there is an odd number of ratings, the median is the middle value, which is 3. Therefore, the median cleanliness rating for Restaurant A is 3.

https://brainly.com/question/12654503

#SPJ3

when you have a problem you can tell me and i can help you

The value of x is 7.63

The formula of the determinant is

x = -b ± √(b² - 4ac) / 2a

Where the equation is in the form of ax² + bx + c = 0

The error made by Peta is to use the determinant formula to find the root of the equation x (x - 5) = 20.

An equation is a mathematical statement that is made up of two expressions connected by an equal sign.

Example:

2x + 4 = 8 is an equation.

We have,

x (x - 5) = 20

Removing the parenthesis.

x² - 5x = 20

x² - 5x - 20 = 0

This is in the form of ax² + bx + c = 0

Now,

a = 1

b = -5

c = -20

Using the determinant formula.

x = -b ± √(b² - 4ac) / 2a

x = 5 ± √(25 + 80) / 2

x = 5 ± √105 / 2

x = (5 + √105) / 2

x = (5 + 10.25) / 2

x = 15.25/2

x = 7.63

x = (5 - √105) / 2

x = (5 - 10.25) / 2

x = -5.25/2

x = -2.63 (neglected)

Thus,

The value of x is 7.63

The error made by Peta is to use the determinant formula to find the root of the equation x (x - 5) = 20.

Learn more about equations here:

https://brainly.com/question/17194269

#SPJ6

Answer: 36ft

Step-by-step explanation: 180*.2=36

Answer:

36 ft

Step-by-step explanation:

to find 20% of 180 ft, multiply 180 ft by 0.20:  0.20(180 ft) = 36 ft

ANSWER

The solution is

(x,y)=(1,-5)

EXPLANATION

The equations are:

1st equation: 6x +5y=-19

2nd equation: 12x-8y=52

Multiply the first equation by 2:

3rd equation: 12x +10y=-38

Subtracy the 2nd equation from the 3rd equations.

12x-12x+10y--8y=-38-52

18y=-90

Divide both sides by 18.

y=-5

Put y=-5 into any of the equations and solve for x.

Preferably, the first equation will do.

6x +5(-5)=-19

6x -25=-19

6x=25-19

6x=6

x=1

The solution is

(x,y)=(1,-5)

Answer:

160

Step-by-step explanation:

The top right quadrant is 90 and the given is 70, adding them equal 160. It is the only option that is greater than 90 degrees anyway.

Answer:

x-intercept: 4  This means that only 4 adults can come under the budjet of $20

y-intercept: 10 This means that only 10 children can come under the budjet of $20

Step-by-step explanation:

for y:

5(0) + 2y = 20

2y = 20

2y/2 = 20/2

y = 10

for x:

5x + 2(0) = 20

5x = 20

5x/5 = 20/5

x = 4

Answer:

The 51 and 62 triangle is 67°

The 43 triangle is 47°

Step-by-step explanation:

Angles in a triangle add to 180°

180 - ( 51 + 62 ) = 180 - ( 113 ) = 67°

180 - ( 43 + 90 ) = 180 - 133 = 47°

Answer:

$ 5674.076

Step-by-step explanation:

The question is on compound interest

The formulae = A= P(1+ r/n) ^nt .......where P is the principal amount, r is the rate of interest in decimal, n is number of compoundings per year and t is the total number of years.

Given; P= $4,000.00 , r=12/100=0.12, n=2 and t=3

Substituting values in the equation  A= P(1+ r/n) ^nt

A= 4000 ( 1+0.12/2)^2×3

A=4000(1.06)^6

A=$ 5674.08

The answer is:

[tex](g\circ f)(0)=-216[/tex]

To composite functions, we need to evaluate functions in another function(s), for example:

Given f(x) and g(x), if we want to calculate f(x) composite g(x), we need to evaluate g(x) into f(x).

So, we are given the functions:

[tex]f(x)=2x-6\\g(x)=x^{3}[/tex]

And we are asked to calculate g(x) composite f(x), and then evaluate "x" to 0, so, calculating we have:

[tex](g\circ f)(x)=g(f(x))\\\\(g\circ f)(x)=(2x-6)^{3}[/tex]

Now that we have the composite function, we need to evaluate "x" equal to 0, so:

[tex](g\circ f)(0)=(2x-6)^{3}\\\\(g\circ f)(0)=(2*(0)-6)^{3}=(0-6)^{3}=-6*-6*-6=-216[/tex]

Hence, we have that:

[tex](g\circ f)(0)=-216[/tex]

Have a nice day!

Answer:

Step-by-step explanation:216

Answer:

7/9

Step-by-step explanation:

6x^3-8y^3-12x^2y^2+4xy       x=2/3 y=1/2

=6(2/3)^3-8(1/2)^3-12(2/3)^2(1/2)^2+4(2/3)(1/2)

=6(8/27)-8(1/8)-12(4/9)(1/4)+4(1/3)

=(16/9)-1-(4/3)+(4/3)

=(1 7/9)-1

=7/9

Answer:

The value of the expression is 100

Step-by-step explanation:

we have

5,200-[40%(300*42.5)]

we know that

(300*42.5)=3*100*42.5=3*4,250=12,750

40%=40/100=0.40

substitute

5,200-[0.40*12,750]

5,200-5,100=100

Answer:

x = 8.9 (nearest tenth)

Step-by-step explanation:

6^2 - 4^2 = 36 - 16 = 20

So

x = 2 * (√20)

x = 2 * 4.47

x = 8.94

Answer:

The value of x = 4√5

Step-by-step explanation:

Points to remember

For a right angled triangle

Hypotenuse² = Base² + Height²

To find the value of x

From the figure we can see a right angled triangle with,

hypotenuse = 6 and height = 4

Value of x = 2 * base

we have, Hypotenuse² =  + Height²

Base² = Hypotenuse² - Height²

 = 6² - 4²

 = 36 - 16  = 20

Base = √20 = 2√5

x = 2 * 2√5 = 4√5

The value of x = 4√5

Answer:

240 units^3

Step-by-step explanation:

To find the volume of a rectangular prism you just multiply length times width times height. So, 8*6*5 which equals 240 units^3.

The dimensions of the prism is given as Length = 8 units, width = 6, Height = 5. Therefore, the volume of the prism is 240 units^3.

Suppose that the right rectangular prism in consideration be having its dimensions as 'a' units, 'b' units, and 'c' units,

then its volume is given as:

[tex]V = a\times b \times c \: \: unit^3[/tex]

The dimensions of the prism is given as

Length = 8 units

width = 6

Height = 5

To find the volume of a rectangular prism

[tex]V = a\times b \times c \: \: unit^3[/tex]

V = 8 x 6 x 5

V = 240 units^3.

Therefore, the volume of the prism is 240 units^3.

Learn more about the volume of a right rectangular prism here:

https://brainly.com/question/21308574

#SPJ2

Answer:

Part 1) The new distance from the water to the top of the tank is [tex]1.979\ in[/tex]

Part 2) The maximum number of balls that can be put into the tank with the tank not overflowing is 95

Step-by-step explanation:

step 1

Find the total volume of the tank

[tex]V=20*10*15=3,000\ in^{3}[/tex]

step 2

Find the volume of the tank if the water level is two inches below the top of the tank

[tex]V=20*10*(15-2)=2,600\ in^{3}[/tex]

step 3

Find the volume of the glass sphere

The volume of the glass sphere is equal to

[tex]V=\frac{4}{3}\pi r^{3}[/tex]

we have

[tex]r=1\ in[/tex]

assume

[tex]\pi=3.14[/tex]

substitute

[tex]V=\frac{4}{3}(3.14)(1)^{3}[/tex]

[tex]V=4.2\ in^{3}[/tex]

step 4

What is the new distance from the water to the top of the tank?

we know that

[tex]2 in -----> represent (3,000-2,600)=400\ in^{3}[/tex]

so

using proportion

Find how many inches correspond a volume of [tex]4.2\ in^{3}[/tex]

[tex]\frac{2}{400}\frac{in}{in^{3}}=\frac{x}{4.2}\frac{in}{in^{3}}\\ \\x=4.2*2/400\\ \\x=0.021\ in[/tex]

The new distance from the water to the top of the tank is

[tex]2-0.021=1.979\ in[/tex]

step 5

Find how many of these balls can be put into the tank with the tank not overflowing

we know that

The volume of one ball is equal to  [tex]4.2\ in^{3}[/tex]

using proportion

[tex]\frac{1}{4.2}=\frac{x}{400}\\ \\x=400/4.2\\ \\x=95.23\ balls[/tex]

therefore

The maximum number of balls that can be put into the tank with the tank not overflowing is 95

Answer:

I think it is A.

Step-by-step explanation:

Hope my answer has helped you!

The true statement is:

Hence, such points could never form a triangle.

Because a triangle is formed with the help of three non-collinear points.

Hence, the points will be coplanar (i.e. they lie in the same plane)

Answer:

22

Step-by-step explanation:

The perimeter of the isosceles triangle with a point of tangency that divides one leg into 3 cm and 4 cm segments is 22 cm, having both legs 7 cm each and the base 8 cm.

Given an isosceles triangle with a point of tangency that divides one of the equal legs into segments of 3 cm and 4 cm, we can determine the perimeter of the triangle by first understanding the properties of such a triangle. The two legs are congruent, and by the Theorem 6, the radius from the center to the point of tangency is perpendicular to the tangent and bisects it. Knowing that the point of tangency divides a leg into two parts, we can denote the entire length of one leg as 3 cm + 4 cm, which equals 7 cm.

Since the triangle is isosceles, both legs are equal in length. This means the other leg is also 7 cm. To find the base, we recall the perpendicular from the center bisects it (Theorem 6). Hence, the base is twice one of the segments, either 3 cm or 4 cm. We will choose the longer segment to ensure that the vertex angles remain acute, and hence the base would be 2 * 4 cm = 8 cm.

Now the perimeter (P) of the triangle can be found by adding the lengths of the two legs and the base: P = 7 cm + 7 cm + 8 cm = 22 cm. Therefore, the perimeter of the isosceles triangle is 22 cm.

For this case we have by definition, that if two lines are parallel then their slopes are equal.

We manipulate the equations algebraically to take them to the form y = mx + b.

Equation 1:

[tex]2y = -3x + 8\\y = - \frac {3} {2} x + 4[/tex]

Thus, the slope of this line is [tex]- \frac {3} {2}.[/tex]

Equation 2:

[tex]6x + 2y = 9\\2y = 9-6x\\2y = -6x + 9\\y = \frac {-6x + 9} {2}\\y = -3x + \frac {9} {2}[/tex]

The slope of this line is -3.

As the slopes are not equal, then the lines are not parallel.

Answer:

False

A line parallel to 2x - 3y = 9 would have the same slope, 2/3, and a different y-intercept, represented as y = (2/3)x + b, where 'b' is any real number.

The equation 2x - 3y = 9 represents a line in a standard form. To find a line that is parallel to it, we need another line with the same slope. The slope-intercept form of the given equation, by isolating y, is y = (2/3)x - 3. A parallel line must have the same slope, which is 2/3 in this case. Therefore, a line parallel to 2x - 3y = 9 could be represented as y = (2/3)x + b, where 'b' is any y-intercept. For example, if b = 5, a parallel line would be given by y = (2/3)x + 5.

Answer:

[tex]96\ basketballs[/tex]

Step-by-step explanation:

step 1

Find the volume of the cylinder (hollow drum)

The volume is equal to

[tex]V=\pi r^{2} h[/tex]

we have

[tex]h=48\ in[/tex]

[tex]r=24\ in[/tex]

substitute

[tex]V=\pi (24)^{2} (48)[/tex]

[tex]V=27,648\pi\ in^{3}[/tex]

step 2

Find the volume of one basketball

The volume of the sphere is equal to

[tex]V=\frac{4}{3}\pi r^{3}[/tex]

we have

[tex]r=6\ in[/tex]

substitute

[tex]V=\frac{4}{3}\pi (6)^{3}[/tex]

[tex]V=288\pi\ in^{3}[/tex]

step 3

Find the maximum number of basketballs that the cylindrical drum contains

so

Divide the volume of the cylinder by the volume of one basketball

[tex]27,648\pi/288\pi=96\ basketballs[/tex]

Answer:

3x + 5y = 105

3x + y = 57

------------------

4y = 48

y = 12, x = 15

{(15, 12)}

Answer:

f(w) = 120 + 5(30-h)

Step-by-step explanation:

It is given that, Andrew gets paid $4 for first 30 hours of the week

So,

For first 30 hours, his wage will be:

4(30) = $120

Now, let w denote wages and h denote total number or hours he works in the week

So he will be paid $5 for h-30 hours

So the function will be

f(w) = 120 + 5(30-h)

Where $120 is the fixed income for first 30 hours and the second term is the wage of hours more than 30 at the rate of $5 per hour..

Answer:

910 yards

Step-by-step explanation:

The total is the yards dyed teal plus the yards dyed indigo:

851 + 59 = 910

Total 910 yards of silk was dyed by the factory for that order.

The addition is defined as a mathematical operation i.e. a method of adding numbers to get total.

We have,

Factory dyed silk teal = 851 yards,

Factory dyed silk indigo = 59 yards,

So,

To get the total we will add the given data,

i.e.

Total silk dyed = dyed silk teal + dyed silk indigo

                        = 851 + 59

                        = 910 yards,

So,

In total 910 yards of silk was dyed by the factory.

Hence, we can say that total 910 yards of silk was dyed by the factory for that order.

To know more about addition click here

https://brainly.com/question/1709448

#SPJ2

Answer:

[tex]\large\boxed{(8\times6)-(4\times2)=48-8=40}[/tex]

The expression (8*2)*2 + 6 + 2 uses the numbers 8, 6, 4, and 2 to equal 40. The question tests knowledge of basic arithmetic operations.

The question involves using the numbers 8, 6, 4, and 2 to create an expression that equals 40. This is a problem dealing with basic arithmetic operations like addition, subtraction, multiplication, and division. The expression can be formed as follows:

So, the expression is: (8*2)*2 + 6 + 2 = 40

https://brainly.com/question/36026091

#SPJ2

Answer:

3.2

Step-by-step explanation:

Calculate the length using the distance formula

d = √ (x₂ - x₁ )² + (y₂ - y₁ )²

with (x₁, y₁ ) = (A(2,2) and (x₂, y₂ ) = B(5, 1)

d = [tex]\sqrt{(5-2)^2+(1-2)^2}[/tex]

  = [tex]\sqrt{3^2+(-1)^2}[/tex]

  = [tex]\sqrt{9+1}[/tex] = [tex]\sqrt{10}[/tex] ≈ 3.2 ( nearest tenth )

Answer:

3.2

Step-by-step explanation:

Distance formula = √ (x₂ - x₁ )² + (y₂ - y₁ )²

Distance = [tex]\sqrt{(5-2)}^{2}  + (1-2)^{2}[/tex]

Distance = [tex]\sqrt{ {3}^{2}  + ( - 1 )^{2}[/tex]

Distance = 3.16227766

Answer:

-5/3, -0.1, 0.7, √2 and √5

Step-by-step explanation:

To start ordering these items, we first need to have a common point of comparison... so we'll get an approximation of their decimal value.  No need to be very precise, just have a rough estimate:

√5: roughly 2.2

-0.1:  -0.1

-5/3: -1.66

0.7: 0.7

√2: roughly  1.4

Now that we have the same comparing point (a decimal value), it's easy to sort them from the smallest value to the greatest value:

-5/3, -0.1, 0.7, √2 and √5

Of course, √2 is smaller than √5

Answer:

[tex]\large\boxed{-\dfrac{5}{3},\ -0.1,\ 0.7,\ \sqrt2,\ \sqrt5}[/tex]

Step-by-step explanation:

[tex]\sqrt5\\\\-0.1=-\sqrt{0.1^2}=-\sqrt{0.01}\\\\-\dfrac{5}{3}=-\sqrt{\left(\dfrac{5}{3}\right)^2}=-\sqrt{\dfrac{25}{9}}=-\sqrt{2\dfrac{7}{9}}\\\\0.7=\sqrt{0.7^2}=\sqrt{0.49}\\\\\sqrt2\\\\-\sqrt{2\dfrac{7}{9}}<-\sqrt{0.01}<\sqrt{0.49}<\sqrt2<\sqrt5[/tex]

Answer:

Option C

Step-by-step explanation:

we know that

Two angles are complements if their sum is equal to 90 degrees

we have that

∠SWT=50°

so

Its complement must be equal to 40 degrees

we know that

∠USP=40°

∠TSV=40°

therefore

∠USP and ∠TSV are complements to ∠ SWT

Answer:

[tex]-11b^2+8b-4[/tex]

Step-by-step explanation:

We can substitute in our expressions for P and Q to get

[tex]P=-4b^2+6b-9\\Q=7b^2-2b-5\\\\(-4b^2+6b-9)-(7b^2-2b-5)[/tex]

Next, we need to distribute the negative to the values within the parenthesis. Then we can combine like terms in order to get our answer

[tex](-4b^2+6b-9)-(7b^2-2b-5)\\\\-4b^2+6b-9-7b^2+2b+5\\\\-11b^2+8b-4[/tex]

Answer:

-11b^2 + 8b - 4

Step-by-step explanation:

(-4b^2 + 6b - 9) - (7b^2 - 2b - 5) =

Drop the first set of parentheses because it is unnecessary. To drop the second set of parentheses, you must distribute the negative sign. That means you must change every sign inside the second set of parentheses.

= -4b^2 + 6b - 9 - 7b^2 + 2b + 5

Now, group like terms.

= -4b^2 - 7b^2 + 6b + 2b - 9 + 5

Finally, combine like terms.

= -11b^2 + 8b - 4

Answer:

Step-by-step explanation:

The total number of marbles is 24 + 36 + 60 = 120

Red: 24/120 = 1/5

Blue: 36/120 = 6/20 = 3/10

Yellow: 60 / 120 = 1/2