Answer:
A. Z = 2 + N13
Step-by-step explanation:
Let's solve your equation step-by-step.
0=z2+4z−9
Step 1: Subtract z^2+4z-9 from both sides.
0−(z2+4z−9)=z2+4z−9−(z2+4z−9)
−z2−4z+9=0
For this equation: a=-1, b=-4, c=9
−1z2+−4z+9=0
Step 2: Use quadratic formula with a=-1, b=-4, c=9.
z=
−b±√b2−4ac
2a
z=
−(−4)±√(−4)2−4(−1)(9)
2(−1)
z=
4±√52
−2
z=−2−√13 or z=−2+√13
(a) The "average value" of a function over an interval [a,b] is defined to be
(1/(b-a)) times the integral of f from the limits x= a to x = b.
Now S = 200(5 - 9/(2+t))
The average value of S during the first year (from t = 0 months to t = 12 months) is then:
(1/12) times the integral of 200(5 - 9/(2+t)) from t = 0 to t = 12
or 200/12 times the integral of (5 - 9/(2+t)) from t= 0 to t = 12
This equals 200/12 * (5t -9ln(2+t))
Evaluating this with the limits t= 0 to t = 12 gives:
708.113 units., which is the average value of S(t) during the first year.
(b). We need to find S'(t), and then equate this with the average value.
Now S'(t) = 1800/(t+2)^2
So you're left with solving 1800/(t+2)^2 = 708.113
<span>I'll leave that to you</span>
Answer:
0.153
Step-by-step explanation:
We have been given that Mafalda has a save percentage of 0.738 so far this hockey season. Last season, her save percentage was 0.585.
To find improvement in Mafalda's save percentage we will subtract last season's save percentage from this season's save percentage.

Therefore, Mafalda's save percentage improved by 0.153.
Answer:
<em>After </em><em>47</em><em> days she will have more than 90 trillion pennies.</em>
Step-by-step explanation:
At the beginning there was 1 penny. At the second day the amount of pennies under the pillow became 2.
The amount of pennies doubled each day. So the series is,

This series is in geometric progression.
As the pennies from each of the previous days are not being stored away until more pennies magically appear so the sum of series will be,

where,
a = initial term = 1,
r = common ratio = 2,
As we have find the number of days that would elapse before she has a total of more than 90 trillion, so









Answer:
9.42 i think
Step-by-step explanation: