The sequence -7 , -5.8 , -4.6 , -3.4 , -2.2 is not a geometric sequence
Step-by-step explanation:
In the geometric sequence, there is a constant ratio between each two consecutive terms
To prove that a sequence is geometric
- Find the ratio between each two consecutive terms
,
,
, .....
- If all the answers give the same ratio, then the sequence is geometric, if not then the sequence is not geometric
The first sequence is 2.8 , 6.72 , 16.128 , 38.7072
∵ = 2.8
∵ = 6.72
∴
∵ = 6.72
∵ = 16.128
∴
∵ = 16.128
∵ = 38.7072
∴
∵ All the ratios above are equal 2.4
∴ The sequence is a geometric sequence
The second sequence is -7, -5.8 , -4.6 , -3.4 , -2.2
∵ = -7
∵ = -5.8
∴
∵ = -5.8
∵ = -4.6
∴
∵ The first two ratios are not equal
∴ The sequence is not a geometric sequence
The third sequence is 1 , -3 , 9 , -27 , 81
∵ = 1
∵ = -3
∴
∵ = -3
∵ = 9
∴
∵ = 9
∵ = -27
∴
∵ = -27
∵ = 81
∴
∵ All the ratios above are equal -3
∴ The sequence is a geometric sequence
The sequence -7 , -5.8 , -4.6 , -3.4 , -2.2 is not a geometric sequence
Learn more:
You can learn more about the geometric sequence in brainly.com/question/1522572
#LearnwithBrainly
