Which expression is the product of (x + 4i)(x − 4i)(x + 4)?
2 answers:
Answer= x³+4x²+16x+64
Expand the following:(x + 4 i) (x - 4 i) (x + 4)
(x - 4 i) (x + 4) = (x) (x) + (x) (4) + (-4 i) (x) + (-4 i) (4) = x^2 + 4 x - 4 i x - 16 i = -16 i + (4 - 4 i) x + x^2:
-16 i + (-4 i + 4) x + x^2 (4 i + x)
| | | | x | + | 4 i
| | x^2 | + | (4 - 4 i) x | - | 16 i
| | | | (-16 i) x | + | 64
| | (4 - 4 i) x^2 | + | (16 + 16 i) x | + | 0
x^3 | + | (4 i) x^2 | + | 0 | + | 0
x^3 | + | 4 x^2 | + | 16 x | + | 64:
Answer: x^3 + 4 x^2 + 16 x + 64
First multiply first 2 elements, so:
(x+4i)*(x-4i) =x^2-16i^2
Now: (x^2-16i^2)*(x+4)=x^3 + 4x^2 - 16xi^2 - 64i^2
You might be interested in
Answer:
x=28
Step-by-step explanation:
vertical angles are congruent
3x-12=72
3x=84
x=28
If his water to cement ratio is 20 to 30, this means that if he uses 20 liters of water, he'd use 30 liters of cement.
The total mixture would then be 20+30=50 liters.
and the water would be 20/50=0.4 or 40% of the total mixture.
Answer:
10
Step-by-step explanation:
Tₙ=n+5
T₅=5+5=10
Answer:
I am willing to help, just send your problems in the comments!
Step-by-step explanation:
You can send the problem in the comments or create a separate question.
Answer: To find the area of a regular polygon, all you have to do is follow this simple formula: area = 1/2 x perimeter x apothem.
Step-by-step explanation: