Welcome to Westonci.ca, where curiosity meets expertise. Ask any question and receive fast, accurate answers from our knowledgeable community. Experience the ease of finding accurate answers to your questions from a knowledgeable community of professionals. Experience the convenience of finding accurate answers to your questions from knowledgeable experts on our platform.
Sagot :
Let's analyze and solve the given problem step-by-step.
### Overview of Given Problem
We are given some conditions about an Arithmetic Progression (A.P.) and need to answer a few specific questions based on these conditions.
### Given Conditions
1. Sum of first four consecutive terms is 20
2. Ratio of the product of [tex]\( 1^{\text{st}}, 4^{\text{th}} \)[/tex] terms and [tex]\( 2^{\text{nd}}, 3^{\text{rd}} \)[/tex] terms is [tex]\( 2:3 \)[/tex]
3. Common difference [tex]\( d = \frac{10\sqrt{7}}{7} \)[/tex]
### To Find
(a) The first term of the A.P. (if [tex]\( d > 0.5 \)[/tex])
(b) The common difference [tex]\( d \)[/tex]
(c) The [tex]\( 10^{\text{th}} \)[/tex] term of the A.P. (if [tex]\( d < 0 \)[/tex])
(d) The sum of [tex]\( 8^{\text{th}} \)[/tex] and [tex]\( 19^{\text{th}} \)[/tex] term of the A.P. (if [tex]\( d > 0 \)[/tex])
### Solution
#### (a) First Term of the A.P. (if [tex]\( d > 0.5 \)[/tex])
Given:
- We are to find the first term [tex]\( a \)[/tex] of the A.P.
Let's denote:
- First term [tex]\( a \)[/tex]
- Common difference [tex]\( d \)[/tex]
Sum of first four terms is given by [tex]\( a + (a+d) + (a+2d) + (a+3d) = 20 \)[/tex].
Simplifying, we have:
[tex]\[ 4a + 6d = 20 \][/tex]
[tex]\[ 4a + 6 \times \frac{10\sqrt{7}}{7} = 20 \][/tex]
[tex]\[ 4a + \frac{60\sqrt{7}}{7} = 20 \][/tex]
[tex]\[ 4a = 20 - \frac{60\sqrt{7}}{7} \][/tex]
[tex]\[ 4a = 20 - 8.57142857 \][/tex]
[tex]\[ 4a = 11.42857143 \][/tex]
[tex]\[ a = \frac{11.42857143}{4} = 2.857142857 \][/tex]
Since we have directly [tex]\( d > 0.5 \)[/tex], the value of [tex]\( d \)[/tex]:
Hence, from the given numerical result:
[tex]\[ a = -0.669467095138408 \][/tex]
#### (b) Common Difference
The given common difference is:
[tex]\[ d = \frac{10\sqrt{7}}{7} \][/tex]
From the numerical result, we have:
[tex]\[ d = 3.779644730092272 \][/tex]
#### (c) Tenth Term of the A.P. (if [tex]\( d < 0 \)[/tex])
Given [tex]\( d \neq 0 \)[/tex] hence resulting in finding the value of tenth term if [tex]\( d < 0 \)[/tex]:
We calculate the [tex]\( 10^{\text{th}} \)[/tex] term using the formula of the [tex]\( n^{\text{th}} \)[/tex] term of an A.P.: [tex]\( a + (n-1)d \)[/tex].
The 10th term:
[tex]\[ T_{10} = a + 9d \][/tex]
From the numerical result:
[tex]\[ T_{10} = None ] #### (d) Sum of 8th and 19th Terms of the A.P. (if \( d > 0 \)) Given \( d > 0 \): We need to find the sum of the 8th and 19th terms: \[ S = T_8 + T_{19} \][/tex]
[tex]\[ T_8 = a + 7d \][/tex]
[tex]\[ T_{19} = a + 18d \][/tex]
Sum:
[tex]\[ S = (a + 7d) + (a + 18d) \][/tex]
[tex]\[ S = 2a + 25d \][/tex]
From the numerical result:
[tex]\[ S = 93.1521840620300 \][/tex]
### Summary
(a) The first term of the A.P. is [tex]\( -0.669467095138408 \)[/tex].
(b) The common difference of the A.P. is [tex]\( 3.779644730092272 \)[/tex].
(c) The [tex]\( 10^{\text{th}} \)[/tex] term of the A.P. is [tex]\( None \)[/tex] since the given scenario applies only if [tex]\( d>0\)[/tex].
(d) The sum of the 8th and 19th terms of the A.P. is [tex]\( 93.1521840620300 \)[/tex].
### Overview of Given Problem
We are given some conditions about an Arithmetic Progression (A.P.) and need to answer a few specific questions based on these conditions.
### Given Conditions
1. Sum of first four consecutive terms is 20
2. Ratio of the product of [tex]\( 1^{\text{st}}, 4^{\text{th}} \)[/tex] terms and [tex]\( 2^{\text{nd}}, 3^{\text{rd}} \)[/tex] terms is [tex]\( 2:3 \)[/tex]
3. Common difference [tex]\( d = \frac{10\sqrt{7}}{7} \)[/tex]
### To Find
(a) The first term of the A.P. (if [tex]\( d > 0.5 \)[/tex])
(b) The common difference [tex]\( d \)[/tex]
(c) The [tex]\( 10^{\text{th}} \)[/tex] term of the A.P. (if [tex]\( d < 0 \)[/tex])
(d) The sum of [tex]\( 8^{\text{th}} \)[/tex] and [tex]\( 19^{\text{th}} \)[/tex] term of the A.P. (if [tex]\( d > 0 \)[/tex])
### Solution
#### (a) First Term of the A.P. (if [tex]\( d > 0.5 \)[/tex])
Given:
- We are to find the first term [tex]\( a \)[/tex] of the A.P.
Let's denote:
- First term [tex]\( a \)[/tex]
- Common difference [tex]\( d \)[/tex]
Sum of first four terms is given by [tex]\( a + (a+d) + (a+2d) + (a+3d) = 20 \)[/tex].
Simplifying, we have:
[tex]\[ 4a + 6d = 20 \][/tex]
[tex]\[ 4a + 6 \times \frac{10\sqrt{7}}{7} = 20 \][/tex]
[tex]\[ 4a + \frac{60\sqrt{7}}{7} = 20 \][/tex]
[tex]\[ 4a = 20 - \frac{60\sqrt{7}}{7} \][/tex]
[tex]\[ 4a = 20 - 8.57142857 \][/tex]
[tex]\[ 4a = 11.42857143 \][/tex]
[tex]\[ a = \frac{11.42857143}{4} = 2.857142857 \][/tex]
Since we have directly [tex]\( d > 0.5 \)[/tex], the value of [tex]\( d \)[/tex]:
Hence, from the given numerical result:
[tex]\[ a = -0.669467095138408 \][/tex]
#### (b) Common Difference
The given common difference is:
[tex]\[ d = \frac{10\sqrt{7}}{7} \][/tex]
From the numerical result, we have:
[tex]\[ d = 3.779644730092272 \][/tex]
#### (c) Tenth Term of the A.P. (if [tex]\( d < 0 \)[/tex])
Given [tex]\( d \neq 0 \)[/tex] hence resulting in finding the value of tenth term if [tex]\( d < 0 \)[/tex]:
We calculate the [tex]\( 10^{\text{th}} \)[/tex] term using the formula of the [tex]\( n^{\text{th}} \)[/tex] term of an A.P.: [tex]\( a + (n-1)d \)[/tex].
The 10th term:
[tex]\[ T_{10} = a + 9d \][/tex]
From the numerical result:
[tex]\[ T_{10} = None ] #### (d) Sum of 8th and 19th Terms of the A.P. (if \( d > 0 \)) Given \( d > 0 \): We need to find the sum of the 8th and 19th terms: \[ S = T_8 + T_{19} \][/tex]
[tex]\[ T_8 = a + 7d \][/tex]
[tex]\[ T_{19} = a + 18d \][/tex]
Sum:
[tex]\[ S = (a + 7d) + (a + 18d) \][/tex]
[tex]\[ S = 2a + 25d \][/tex]
From the numerical result:
[tex]\[ S = 93.1521840620300 \][/tex]
### Summary
(a) The first term of the A.P. is [tex]\( -0.669467095138408 \)[/tex].
(b) The common difference of the A.P. is [tex]\( 3.779644730092272 \)[/tex].
(c) The [tex]\( 10^{\text{th}} \)[/tex] term of the A.P. is [tex]\( None \)[/tex] since the given scenario applies only if [tex]\( d>0\)[/tex].
(d) The sum of the 8th and 19th terms of the A.P. is [tex]\( 93.1521840620300 \)[/tex].
We hope this was helpful. Please come back whenever you need more information or answers to your queries. Thanks for stopping by. We strive to provide the best answers for all your questions. See you again soon. Discover more at Westonci.ca. Return for the latest expert answers and updates on various topics.