Answer:
As the temperature rises the sales increase
Step-by-step explanation:
Answer:
The explicit rule of the geometric sequence
aₙ = 187.5 (0.8)ⁿ⁻¹
Step-by-step explanation:
<u><em> Step(i):-</em></u>
Given that the third term of the sequence = 120
tₙ = a rⁿ⁻¹
t₃ = a r³⁻¹ = ar²
120 = ar² ..(i)
Given that the fifth term of the given geometric sequence = 76.8
tₙ = a rⁿ⁻¹
t₅ = a r⁵⁻¹ = a r⁴
76.8 = a r⁴...(ii)
<u><em>Step(ii):</em></u>-
Dividing (ii) and (i)

r² = 0.64
r =√ 0.64 = 0.8
Substitute r= 0.8 in equation (i)
120 = ar²
120 = a(0.8)²
⇒ 
<u><em>Step(iii):-</em></u>
The explicit rule of the geometric sequence
aₙ = a rⁿ⁻¹
put a= 187.5 and r = 0.8
aₙ = 187.5 (0.8)ⁿ⁻¹
let's put value of t in equation.
x = 2√t
x = 2√y
x/2 = √y
(x/2)^2 = y
y = x^2 /4
now let's differentiate it with respect to x.
dy/dx = 2x/4 = x/2
differentiating again wrt to x
d^2y/dx^2 = 1/2
The value of x in the traingle is 5
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