Answer:
Step-by-step explanation:
From the question, Diana wants her total bill to be less than $50.
Diana pays a fixed monthly bill of
$39 for her mobile phone and an additional
$0.15 per minute for phone internet service.
The bill Diana pays for m minutes of using the internet is $0.15m in a month.
The total monthly bill becomes,
The maximum bill she wants to pay is $50.
This inequality can be solved to determine the number of available minutes.
Answer:
Using either method, we obtain:
Step-by-step explanation:
a) By evaluating the integral:
The integral itself can be evaluated by writing the root and exponent of the variable u as:
Then, an antiderivative of this is:
which evaluated between the limits of integration gives:
and now the derivative of this expression with respect to "t" is:
b) by differentiating the integral directly: We use Part 1 of the Fundamental Theorem of Calculus which states:
"If f is continuous on [a,b] then
is continuous on [a,b], differentiable on (a,b) and
Since this this function is continuous starting at zero, and differentiable on values larger than zero, then we can apply the theorem. That means:
