145k views
5 votes
Can you help me with this ?! !!

Can you help me with this ?! !!-example-1
User Eloisa
by
7.5k points

1 Answer

4 votes

Explanation:

remember,

x^-n = 1/x^n

any negative exponent of 1.3 means we have to consider it as 1/1.3 with the positive exponent.

so, if the given temperature (x) is negative, 1.3 has a positive exponent and gets bigger and bigger the lower (smaller) x gets.

if the given temperature (x) is positive, 1.3 has a negative exponent and gets smaller and smaller the higher (bigger) x gets.

the domain is the interval or set of all valid x-values.

there is no need for any restriction for x.

so, the domain is all real numbers.

the question is : up to what temperature will there be heating ?

at 5°C ? yes, sure.

at 10°C ? yes, sure.

at 15°C ? some people still need heating.

at 20°C ? most likely not.

but f(20) = $0.042094266... ≈ $0.04

so, still a tiny little bit of heating is happening for the function, but in reality most likely not at all.

the information about such a limit is missing in the question. so, again no limit for x.

f(-8) means that x = -8.

f(-8) = 8(1.3)^--8 = 8(1.3)⁸ = 8×8.15730721 =

= 65.25845768

when the low outside temperature is -8°C, it would cost $65.26 to heat the building.

I don't know the answer options to the last part, but the interpretation certainly is in the context of the problem.

User PaulAdamDavis
by
8.7k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories