Answer:
x³ + x² − 4x + 6 = 0
Step-by-step explanation:
Imaginary roots come in conjugate pairs. So if 1+i is a root, then 1−i is also a root.
(x − (-3)) (x − (1+i) (x − (1−i)) = 0
(x + 3) (x² − (1+i) x − (1−i) x + (1+i) (1−i)) = 0
(x + 3) (x² − x − ix − x + ix + 1 − i²) = 0
(x + 3) (x² − 2x + 2) = 0
x (x² − 2x + 2) + 3 (x² − 2x + 2) = 0
x³ − 2x² + 2x + 3x² − 6x + 6 = 0
x³ + x² − 4x + 6 = 0
For this case we first write the equation of which we will use:
I (db) = 10log (l / l)
We substitute the value of l.
We have then:
l = 10 ^ 8lo
Substituting in the given equation:
I (db) = 10log ((10 ^ 8lo) / lo)
Rewriting:
I (db) = 10 * log (10 ^ 8)
I (db) = 80
Answer:
I (db) = 80
option 4
The answer is 64. You don’t know x so you need to take the two and multiply 8. 8 times 8 equals 64
When you solve a proportion, your first step should be to cross-multiply.
=
When you cross-multiply, you should get this equation:
(2x)(3) = (x + 3)(5)
Now, solve it using algebra.
(2x)(3) = (x + 3)(5) Multiply
6x = 5x + 15 Subtract 5x from both sides
x = 15
The value of
x is 15.
Answer:
17.3 years
Step-by-step explanation:
For some annual interest rate r and time in years t, the initial account value is multiplied by e^(rt).
You want the multiplier e^(.04t) to have a value of 2:
2 = e^(.04t)
ln(2) = 0.04t . . . . . take natural logs
t = ln(2)/0.04 = 17.329 . . . . . divide by the coefficient of t
It will take about 17.3 years for the investment to double.
