Answer:
A(t) = 90e^0.12t ;
299 mg
Step-by-step explanation:
General Continous growth rate equation :
A = Pe^rt
A = amount present, t years after year of initial amount.
Here,
P = 90 mg, amount in year 2000
r = rate = 12% = 0.12
t = years after 2000
Therefore,
A is written as ;
A(t) = 90e^0.12t
Amount present in year 2010 ;
t = 2010 - 2000 = 10
A(10) = 90e^0.12(10)
A(10) = 90 * e^1.2
= 90 * 3.3201169
= 298.81052
= 299 mg
Answer:
See below.
Step-by-step explanation:
First, notice that this is a composition of functions. For instance, let's let
and
. Then, the given equation is essentially
. Thus, we can use the chain rule.
Recall the chain rule:
. So, let's find the derivative of each function:

We can use the Power Rule here:
Now:

Again, use the Power Rule and Sum Rule

Now, we can put them together:


Bet what is it?................
2(2t + 4) = 34(24 − 8t)
4t + 8 = 816 - 272t
4t + 272t = 816 - 8
276t = 808
t = 808/276
= 2.93 (to three significant figures)
The value of t is 2.93.
Step-by-step explanation:
the error:
it is stated that
subtract (5x)/(x+7) from both sides

multiply both sides by x + 7
7(x+7) = 49x
7x + 49 = 49x
subtract 7x from both sides to isolate x and its coefficient
49 = 42x
thus, this is only true when 49 = 42x. in order for these two equations to be equal, they must <em>always </em>be true, so this is wrong
the solution:
we want to express 7/x as (something) / (x+7). to do this, we can multiply 7/x by 1.
anything divided by itself = 1. thus, if we multiply both the numerator and the denominator by something that turns x into (x+7), we can do what we want to do.
(x+7)/x * x turns x into (x+7), so we multiply both the numerator and denominator by (x+7)/x to get

substitute this for 7/x in our original problem
