Quadratic Equations and Complex Numbers Flashcards
1
Q
Difference of squares
A
a² - b² = (a+b)(a-b)
2
Q
How to solve a binomial with an exponent that isn’t 1
A
- Multiply the x² by the last number without x
- Find the two numbers that add up to the middle number and multiply to the new last number
- Keep the old last number in the new equation
3
Q
How to find the zeros in a binomial
A
Factor the equation and solve each x with zero
4
Q
Complex number
A
a+bi
5
Q
What is a in a+bi
A
The real portion
6
Q
What is bi in a+bi
A
The imaginary portion
7
Q
What is √-1
A
i
8
Q
What is i²
A
-1
9
Q
What is the complex conjugate?
In imaginary factorials
A
(a+bi)(a-bi)
10
Q
How to divide complex numbers
A
Multiply the top and bottom by the conjugate
(the opposite)
Ex. 3x-2; 3x+2
11
Q
Every _ power of i; the pattern repeats itself
A
4th
12
Q
What is the pattern of i
A
1
i
-1
-i
13
Q
Steps to find what i to a power equals
A
- Divide the exponent by 4
- Remainder is the answer to the problem
14
Q
What is a conjugate?
A
The same numbers but opposite addition/subtraction
15
Q
How to complete the square
A
- a must = 1
- put a and b on the same side and c on the opposite side
- (b/2)²
- Factor
- Solve