Answer:
D
Step-by-step explanation:
Let's substitute a for x²:
x^4 - 3x² - 4
a² - 3a - 4
Now, this looks like something that is much more factorisable:
a² - 3a - 4 = (a - 4)(a + 1)
Plug x² back in for a:
(a - 4)(a + 1)
(x² - 4)(x² + 1)
The first one is a difference of squares, which can be factored into:
x² - 4 = (x + 2)(x - 2)
The second one can also be treated as a difference of squares:
x² + 1 = x² - (-1) = (x + √-1)(x - √-1) = (x + i)(x - i)
The answer is (x + 2)(x - 2)(x + i)(x - i), or D.
Subtract 3n and then divide by 4 and you get n= 4
Answer:
This is what I got, the second one, the third one, and the fifth one.
Step-by-step explanation:
I'll assume the ODE is actually

Look for a series solution centered at
, with



with
and
.
Substituting the series into the ODE gives





- If
for integers
, then




and so on, with

- If
, we have
for all
because
causes every odd-indexed coefficient to vanish.
So we have

Recall that

The solution we found can then be written as

