how prove the following
cos²(120°-A) + cos²A + cos²(120°+A)= 3/2
​

Answer: 5 s

Step-by-step explanation:

Given

Height of the rocket can be modelled as [tex]h=80-16t^2[/tex]

Rocket will land on earth when it's height becomes 0

[tex]\Rightarrow 80t-16t^2=0\\\Rightarrow t(80-16t)=0\\\\\Rightarrow t=0\ \text{or}\ t=\dfrac{80}{16}=5\ s[/tex]

Neglecting 0 value

Thus, rocket remains in air for 5 s.

It looks like the equation is

-sin²(x) = cos(2x)

Recall the half-angle identity for sine:

sin²(x) = (1 - cos(2x))/2

Then the equation can be written as

-(1 - cos(2x))/2 = cos(2x)

Solve for cos(2x):

-1/2 + 1/2 cos(2x) = cos(2x)

-1/2 = 1/2 cos(2x)

cos(2x) = -1

On the unit circle, cos(y) = -1 when y = arccos(-1) = π. Since cosine has a period of 2π, more generally we have cos(y) = -1 for y = π + 2nπ where n is any integer. Then

2x = π + 2nπ

x = π/2 + nπ

In the interval [-π, π], you get two solutions x = -π/2 and x = π/2.

Answer:

15/2 that is the answer man

Answer:

no change in area

Step-by-step explanation:

The original area is

A = 12*5 = 60 ft^2

The new length and width

l = 12 + .25 (12) = 12+3 =15

w = 5 - .2 (5) =5-1 = 4

The new area is

A = l*w =15*4 = 60 ft^2

The area is the same

Answer:

step number 1 is incorrect.

Step-by-step explanation:

Here is the solution of this equation [2x-31-1=2].

2x-31-1=2

or 2x-31=2+1

or 2x=2+1+31

or 2x= 34

or x=34/2

or x= 17

the answer of this equation is X=17.

Answer:

Step 1

Step-by-step explanation:

Answer:

Step-by-step explanation:

Total amount with Gerald = $32

Cost of fuel per gallon = $2.75

Cost of each bottle of windshield = $3

38 miles per gallon. If Gerard must fill his car with enough fuel to drive 250 miles,

Total gallons of fuel = 250 miles / 38 miles

= 6.5789473684210 gallons

Total cost of fuel = Total gallons of fuel × cost per gallon

= 6.5789473684210 × $2.75

= $18.1

Amount left for windshield = Total amount with Gerald - Total cost of fuel

= $32 - $18.1

= $13.9

what is the maximum number of bottles of windshield washer fluid Gerard can buy?

= Amount left for windshield / Cost of each bottle of windshield

= $13.9 / $3

= 4.6333333333333 bottles

Maximum number of bottles =

4 bottles

Answer:

f the answer to the question is A

Answer:b

Step-by-step explanation:

Answer:

y + 2.3 = 0.45x

y = 0.45x - 2.3

-2y = 4.2x - 7.8

-2(0.45x - 2.3) = 4.2x - 7.8

-0.90x + 4.6 = 4.2x - 7.8

-0.90x - 4.2x = -7.8 - 4.6

-5.1x = - 12.4

x = -12.4 / -5.1

x = 2.4

y + 2.3 = 0.45x

y = 0.45(2.4) - 2.3

y = 1.08 - 2.3

y = -1.2

solution is : (2.4, - 1.2)

Step-by-step explanation:

Answer:

$9.04 /gal

Step-by-step explanation:

1 gallon = 128 oz

8 * 4.23 oz = 33.84 oz

$2.39 /33.84 oz = .0707 $/oz

 .0707 $/oz * 128 = $9.04 $/gal

Explanation:

The probability of picking red is 0.13

The probability of picking orange is 0.20

The probability of picking either of these is 0.13+0.20 = 0.33

So the probability of picking neither of them is 1 - 0.33 = 0.67

There's a 67% of this happening.

Answer:

0.34

Step-by-step explanation:

because the probability of red is 20 and the probability of orange is 14 20 + 14 is 34.

Answer:

−48x+112

Step-by-step explanation:

evatulate: −16  (3−7)

                -48+112

Answer:

Side-Side-Side (SSS)

Step-by-step explanation:

Side-Side-Side is a rule used to prove whether a given set of triangles are congruent. The SSS rule states that: If three sides of one triangle are equal to three sides of another triangle, then the triangles are congruent.

Answer:

Answer is in attached image

I hope it help...

Step-by-step explanation:

p = 2×( l+w)

p = 2×l + 2×w

=> 2×w = p - 2×l

w = (p - 2×l) / 2

w = (11 - (2×2.8))/2

= (11- 5.6)/2

= 5.4 /2

= 2.7 cm

Answer:

Equation:  [tex]70=(x+3)x[/tex]

x = -10 or x = 7

x = 7 (width can't be negative)

x + 3 = 10

Step-by-step explanation:

Represent the width of the rectangle by  x.  "The length of a rectangle EXCEEDS the width by 3" means the length is 3 LONGER than the width, so the length is represented by the expression  x + 3.

Area = (length)(width)

70 = (x + 3)x

Multiply out the right side.

[tex]70=x^2+3x\\x^2+3x-70=0[/tex]

Factor the left side.

[tex](x+10)(x-7)=0[/tex]

Each binomial could equal 0, so

[tex]x+10=0 \text{ or }x-7=0\\x=-10\text{ or }x=7[/tex]

The negative solution does not make sense as the width of a rectangle.

x = 7, making the length, x + 3 = 10

Answer:

Pls mark this as brainiest

Step-by-step explanation:

Area of the rectangle = length x breadth

consider 'x' to be width

therefore length = x+3

area = (x+3)*x

Area = 70 square

x = 7

x+3 = 7+3

      = 10

verification

7 x 10

= 70

Answer:

G. 4 cm

Step-by-step explanation:

28 divided by 7 equals 4.

So, 16 divided by 4 equals 4, which is the answer.

4 is the multiple that relates AABC to ADEF.

Answer:

(x, y) = (5,8)

Step-by-step explanation:

Comparing the ordered pairs we get, x+y=13 and 2=2x-y. Solving it we will get, x=5 and y=8

The given relation {(2,1), (4,2) (6,3) (8,4)} is one to many relation.

The other solution for this problem is given below.

The pattern is the sum of the two numbers plus the previous sum, i.e.

12 = 2+5 +(5)

21 = 3+6+ (12)

40 = 8+11 +21

These type of questions are part of reasoning and comes in random competitive exams which have multiple choice questions and therefore you have more than you want.

First , you need to multiply both numbers and then add the first number.

Therefore, 1+4= 1x4+1=5

2+5=2×5+2=12

3+6=3×6+3=21

A many-to-one relationship is where one entity (typically a column or set of columns) contains values that refer to another entity (a column or set of columns) that has unique values.

Hence,8+11=8×11+8=96

The other solution for this problem is given below.

The Solution for this is

1+4=5

1(4+1)=1(5)=5

2+5=12

2(5+1)=2(6)=12

3+6=21

3(6+1)=3(7)=21

Therefore we get,

8+11=8(11+1)=8(12)=96.

Therefore the given relation is any one to many relation.

To learn more about the relation visit:

https://brainly.com/question/1579288

Answer:

6+2+(32×2)

6+2+(64)

8+64

72

difference between 72 and 28

72-28

=44

add 44 to make the value 28

Answer:

Hello,

Answer B (-5/3,-4/3)

Step-by-step explanation:

I am going to use the substitution 's method.

[tex]\left\{\begin{array}{ccc}x+y&=&-3\\y&=&2x+2\\\end {array} \right.\\\\\\\left\{\begin{array}{ccc}y&=&2x+2\\x+2x+2&=&-3\\\end {array} \right.\\\\\\\left\{\begin{array}{ccc}y&=&2x+2\\3x&=&-5\\\end {array} \right.\\\\\\\left\{\begin{array}{ccc}x&=&-\dfrac{5}{3} \\\\y&=&2*(-\dfrac{5}{3})+2\\\end {array} \right.\\\\\\\boxed{\left\{\begin{array}{ccc}x&=&-\dfrac{5}{3} \\\\y&=&-\dfrac{4}{3}\\\end {array} \right.\\}[/tex]

Answer:

[tex]\displaystyle d = \sqrt{29}[/tex]

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Algebra I

Algebra II

Step-by-step explanation:

*Note:

The distance formula is derived from the Pythagorean Theorem.

Step 1: Define

Identify

Point (5, 10)

Point (10, 12)

Step 2: Find distance d

Answer:

Volume is equal to

L×W×H

=(10×9×7)cm

=90×7

=630

The volume of the prism is 980cm3.

We are given that;

The dimensions= 4*7*9*2*10cm

Now,

A rectangular prism is a three-dimensional shape that has two at the top and bottom and four are lateral faces.

The volume of a rectangular prism=Length X Width X Height

Volume of upper prism;

=5*4*40

=800cm3

Volume of lower prism;

=2*9*10

=180cm3

Total volume= upper volume + lower volume

=980cm3

Therefore, by the rectangular prism the answer will be 980cm3.

Learn more about a rectangular prism;

https://brainly.com/question/21308574

#SPJ2

Answer:

31.50 mm²

Step-by-step explanation:

A trapezoid is a convex quadrilateral. A trapezoid has at least on pair of parallel sides. the parallel sides are called bases while the non parallel sides are called legs

Characteristics of a trapezoid

It has 4 vertices and edges

If both pairs of its opposite sides of a trapezoid are parallel, it becomes a parallelogram

Area of a trapezoid =  1/2 x (sum of the lengths of the parallel sides) x height

1/2 x ( 7.3 + 5.3) x 5 = 31.50 mm²

Answer:

Students Major

Cheat reporting response

Number of Alcohols taken

Student's Height

Step-by-step explanation:

The Variables are the following:

Categorical variables

1. Major – The student's majors -

Arts & Social Science or STEM

2. Cheat - Response about reporting cheating - Yes or No

Quantitative Variables

3. Alcohol - Number of alcoholic beverages consumed in a typical week

4. Height - Self-reported height (in inches)

Answer:

total candy = 54 bags

y=17

x=37

Step-by-step explanation:

5x + 4y = 253

x-y = 20

x = 20+y

5(20+y) + 4y = 253

100 + 9y = 253

9y = 153

y=17

x=37

Answer:

Step-by-step explanation:

days in september=30

salry paid per day=Rs.160

salary paid in 30 days=160×30=Rs.4800

Answer:

4800

Step-by-step explanation:

In the month of September there are only 30 days. So assuming Sohanlal works the entire month of September we will multiply how much he makes daily which is 160 times the amount of days he works which is 30. this will look like this:

160 × 30 = 4800

Answer:

x=-1  y = 1/3

x = 1  y = 3

x = 3  y = 27

Step-by-step explanation:

y = 3^x

Let x = -1

y = 3^-1 = 1/3^1 = 1/3

Let x = 1

y = 3^1 = 3

Let x = 3

y = 3^3 = 27

Given:

The recursive formulae.

To find:

The correct explicit formulae for the given recursive formulae.

Solution:

If the recursive formula of a GP is [tex]f(n)=rf(n-1), f(1)=a, n\geq 2[/tex], then the explicit formula of that GP is:

[tex]f(n)=ar^{n-1}[/tex]

Where, a is the first term and r is the common ratio.

The first recursive formula is:

[tex]f(1)=5[/tex]

[tex]f(n)=3f(n-1)[/tex] for [tex]n\geq 2[/tex].

It is the recursive formula of a GP with a=5 and r=3. So, the required explicit formula is:

[tex]f(n)=5(3)^{n-1}[/tex]

Therefore, the required explicit formula for the first recursive formula is [tex]f(n)=5(3)^{n-1}[/tex].

If the recursive formula of an AP is [tex]f(n)=f(n-1)+d, f(1)=a, n\geq 2[/tex], then the explicit formula of that AP is:

[tex]f(n)=a+(n-1)d[/tex]

Where, a is the first term and d is the common difference.

The second recursive formula is:

[tex]f(1)=5[/tex]

[tex]f(n)=f(n-1)+5[/tex] for [tex]n\geq 2[/tex].

It is the recursive formula of an AP with a=5 and d=5. So, the required explicit formula is:

[tex]f(n)=5+(n-1)5[/tex]

[tex]f(n)=5+5(n-1)[/tex]

Therefore, the required explicit formula for the second recursive formula is [tex]f(n)=5+5(n-1)[/tex].

The third recursive formula is:

[tex]f(1)=5[/tex]

[tex]f(n)=f(n-1)+3[/tex] for [tex]n\geq 2[/tex].

It is the recursive formula of an AP with a=5 and d=3. So, the required explicit formula is:

[tex]f(n)=5+(n-1)3[/tex]

[tex]f(n)=5+3(n-1)[/tex]

Therefore, the required explicit formula for the third recursive formula is [tex]f(n)=5+3(n-1)[/tex].