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Identity:

An identity is an equality which is true for all values of a variable in the equality.

(a + b)³ = a³+ b³+ 3ab(a + b)

In an identity the right hand side expression is called expanded form of the left hand side expression.

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Solution:

(i) (2x + 1)³

Using identity

(a + b)³ = a³+ b³+ 3ab(a + b)

(2x + 1)³

= (2x)³ + 1³ + (3×2x×1)(2x + 1)

= 8x³+ 1 + 6x(2x + 1)

= 8x³ + 1 + 12x² + 6x

(ii) (2a – 3b)³

Using identity,

(a – b)³ = a³–b³ – 3ab(a – b)

(2a – 3b)³ = (2a)³– (3b)³ – (3×2a×3b)(2a – 3b)

=8a³–27b³–18ab(2a –3b)

= 8a³–27b³–36a²b + 54ab²

(iii) [3x/2  + 1]³

Using identity,

(a + b)³ = a³+ b³+ 3ab(a + b)

[3x/2 +1]³

=(3x/2)³+1³+ (3×(3x/2)×1)(3x/2+ 1)

=27x³/8+1+9/2x×(3x/2+1)

= 27x³/8 + 1 + 27/4 x² + 9/2x

= (27/8)x³ + (27/4) x² + 9/2 x + 1

(iv) [x–2/3 y]³

Using identity,

(a - b)³=a³-b³-3ab(a-b)

(X+ 2/3y)³

= (x)³–(2/3 y)³– (3×x×2/3 y)(x – 2/3 y)

= x³– 8y³/27–2xy(x – 2/3 y)

= x³– (8/27)y³–2x²y+ 4/3xy²

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Hope this will help you....

Step-by-step explanation:

Answer:

16 rs maybe not sure sry if wrong

Answer:

[tex] = 2\pi \: r \: h \\ 2 \times \pi \times 4 \times 9 \\ = 226 .19 {cm}^{2} [/tex]

Can I have the brainliest please?

Answer:

9 X 4 = 36

Step-by-step explanation:

not really the answer sorry pls dont be mad

Answer:

726

Step-by-step explanation:

66*22/2=726

Answer:

300

Step-by-step explanation:

im smart

Answer:

C. 20 x 4 = 1/5Step-by-step explanation:

Answer:

The answer is C

Step-by-step explanation:

4/20=.02 so its not A

1/5 divided by 4 is .05

So that leaves C

I hope this helps :)

Step-by-step explanation:

4/7÷21/3

=4/7*3/21

=12/147

Answer:

[tex]\frac{12}{49}[/tex]

Step-by-step explanation:

Given

[tex]\frac{4}{7}[/tex] ÷ 2 [tex]\frac{1}{3}[/tex] ← change mixed number to improper fraction

= [tex]\frac{4}{7}[/tex] ÷ [tex]\frac{7}{3}[/tex]

To perform the division

Leave the first fraction. change division to multiplication and turn the second fraction upside down.

= [tex]\frac{4}{7}[/tex] × [tex]\frac{3}{7}[/tex] ← multiply numerators/ denominators together

= [tex]\frac{4(3)}{7(7)}[/tex]

= [tex]\frac{12}{49}[/tex]

Answer:

Done :)

Step-by-step explanation:

Best of luck!

Answer:

cubic hahahabqbnqnwnw

Answer:

4.41seconds later

Step-by-step explanation:

Let the equation of the height reached by the water front be h = -2t^2+7t+4

The water hits the ground at h =0

Substitute

0 =  -2t^2+7t+4

-2t^2+7t+4 = 0

2t^2 - 7t - 8 = 0

t = 7±√(-7)²-4(2)(-8)/2(2)

t = 7±√49+64/4

t = 7±√113/4

t = 7±10.63/4

t = 7+10.63/4

t = 17.3/4

t = 4.41s

Hence the water hit the ground 4.41seconda later

Answer:

1. -3/2

2. 8

Step-by-step explanation:

Plug the number in with x to find the answer, then solve using PEMDAS as normal.

Answer:

Step-by-step explanation:

Car 2 is traveling faster than Car 1. Option B is correct.

Given that,
The table and equation below show the proportional relationship between time, in seconds, x, and distance traveled, in feet, y, for two remote-control cars.

Speed is defined as when an object is in motion, the distance covered by that object per unit of time is called speed.

here,
Speed of the car 1,
= 85 - 75 / 17 - 15
= 10 / 2
= 5 feet/second

Speed of the car 2,
y = 10x
Where 10 is the speed of the car 2 feet per second.
So,
Speed of the car 2  is faster than car 1.

Thus,  Car 2 is traveling faster than Car 1. Option B is correct.

Learn more about speed here:
https://brainly.com/question/7359669

#SPJ5

Answer:

1200

Step-by-step explanation:

400 x 300 because double

Answer: The property sold for $5,870.41.

Step-by-step explanation:

Let x be the selling price of the property.

Then, gross commission = 6.5% of x = 0.065x

listing salesman received = 12% of ( 0.065x)  = 0.12 (0.065x) = 0.0078 x

Balance = x - ( 0.065x) -  (0.0078 x)

= (1+0.065-0.0078)x

= 1.0572x

Scott received = 45% of (1.0572x)

=0.45 (1.0572x)

= 0.47574x

Now, [tex]0.47574x=2,792.79[/tex]

[tex]\Rightarrow\ x=\dfrac{2792.79}{0.47574}\\\\\Rightarrow\ x=5870.41[/tex]

Hence, the property sold for $5,870.41.

Answer:

11/24

Step-by-step explanation:

Answer:

11/24

Step-by-step explanation:

Answer: x=2±√10 or x=5.16227766

Step-by-step explanation:

Answer:

b. $2.65

Step-by-step explanation:

$10.00 - $7.35 = ?

$10.00 - $7.35 = $2.65

Answer:

your answer would be b. $2.65

Find multiples of 30 and 40:

30: 30, 60, 90, 120, 150

40: 40, 80, 120, 160

The least common multiple is 120, so every 120 minutes they willl both ring.

1 hour = 60 minutes:

120/60 = 2 hours.

The bells ring together every 2 hours.

8 + 2  = 10 am

10 +  = 12pm

12 + 2 = 2 pm

The bells will ring together at am, 12 pm and 2 pm.

Answer:

At first common multiple of 30 an 40

[tex] \sf \to \: 30 = 30,60,90,120[/tex]

[tex] \sf \to \: 40 = 40,80,120[/tex]

Common Multiple = 120

Time taken = 120/60 = 2 hrs

Now,

8.00 + 2 = 10.00 am

10.00 + 2 = 12.00 noon

12.00 + 2 = 2.00 pm

[tex] \\ [/tex]

Answer:

Step-by-step explanation:

the x is 30

60=2x

x=30

Answer:

d

Step-by-step explanation:

its d i think

Answer:

6

Step-by-step explanation:

I'm going to assume that this is a right triangle

which means that

3x²+6²=19²

9x²+36=361

9x²=325

3x=18.0277

x=6

Answer:

74.2 million children under the age of 18

Step-by-step explanation:

Answer:

74•2 million kids are in the usa

Answer:

2/5, 3/7, and 2/11

Step-by-step explanation:

Answer:

4sinA+3cosA=5 look at this answer.sorry if wrong.i am not sure.

Answer:

masamstha 31 deleted account is correct hope it's help you have a great day ☺☺

Answer:

4

Step-by-step explanation:

Answer:

5cm

Step-by-step explanation:

V = (B*H)

90 = (18 * H)

H = 90 / 18