Solve for x plz help

A. [4 marks]

storchak [24]

The value of d is -2

Step-by-step explanation:

The nth term of the arithmetic sequence is $u_{n}=u_{1}+(n-1)d$ , where

$u_{1}$ is the first term
d is the common difference between each 2 consecutive terms

The nth term of the geometric sequence is $u_{n}=u_{1}r^{n-1}$ , where

$u_{1}$ is the first term
r is the common ratio between each two consecutive terms $r=\frac{u_{2}}{u_{1}}=\frac{u_{3}}{u_{2}}$

∵ $u_{1}$ of an arithmetic sequence is 1

∵ The common difference is d, where d ≠ 0

∵ $u_{2}$ , $u_{3}$ , $u_{6}$ are the first 3 terms of a geometric sequence

∵ $u_{2}$ = 1 + (2 - 1)d

∴ $u_{2}$ = 1 + d

∵ $u_{3}$ = 1 + (3 - 1)d

∴ $u_{2}$ = 1 + 2d

∵ $u_{6}$ = 1 + (6 - 1)d

∴ $u_{2}$ = 1 + 5d

∴ The first 3 terms of the geometric sequence are (1 + d) , (1 + 2d) ,

(1 + 5d)

∵ The common ratio in the geometric sequence is $r=\frac{u_{2}}{u_{1}}=\frac{u_{3}}{u_{2}}$

∴ $r=\frac{1+2d}{1+d}=\frac{1+5d}{1+2d}$

- Use cross multiplication with the equal fractions

∵ $\frac{1+2d}{1+d}=\frac{1+5d}{1+2d}$

∴ (1 + 2d)(1 + 2d) = (1 + d)(1 + 5d)

∴ 1 + 2d + 2d + 4d² = 1 + 5d + d + 5d²

- Add like terms in each side

∴ 1 + 4d + 4d² = 1 + 6d + 5d²

- Subtract 1 from both sides

∴ 4d + 4d² = 6d + 5d²

- Subtract 4d from both sides

∴ 4d² = 2d + 5d²

- Subtract 4d² from each side

∴ 0 = 2d + d²

- Take d as a common factor

∴ 0 = d(2 + d)

- Equate each factor by 0

∴ d = 0 but we will reject it because d ≠ 0

∴ 2 + d = 0

- Subtract 2 from both sides

∴ d = -2

The value of d is -2

Learn more:

You can learn more about the sequence in brainly.com/question/1522572

#LearnwithBrainly

7 0

3 years ago

What is the relationship between the continental drift hypothesis and the theory of

Pepsi [2]

Answer:

Plate tectonics explains why Earth's continents are moving; the theory of continental drift did not provide an explanation. Therefore, the theory of plate tectonics is more complete. It has gained widespread acceptance among scientists.

Step-by-step explanation:

Do some research on it.

5 0

2 years ago

Suppose the first term of a geometric sequence is 3 and the fourth term is 192. What is the common ratio of the sequence? Write

gayaneshka [121]

An=A1 r ^(n-1)
192= 3 r ^(4-1)
192 = 3 r^3
64 = r^3
r = 4

equation:
An=3 (4)^(n-1)

6th term:
An= 3 (4)^(6-1)
An= 3072

I think this is right :)

3 0

3 years ago

Ng

Feliz [49]

Answer:

PRT%

Step-by-step explanation:

PRT

$= 320 \times 2.3 \times 20 \div 100 = 1472$

5 0

2 years ago

The formula for the perimeter, P, of a rectangle is P = 2L + 2w, where L is the length and W is th width sovle the formula for t

vichka [17]

P = 2L + 2w

Subtract 2L
from each side: P - 2L = 2w

Divide each side
by 2 : (P - 2L) / 2 = w

You could also write it as (P/2 - L) = w
Both answers are the same.

4 0

3 years ago