Answer:
x = -3 and x = -3/2
Step-by-step explanation:
After writing down the polynomial, split it; put a line between 3x^2 and -18x. Look and 2x^3 + 3x^2 and -18x - 27 separately and factor them both:
p(x) = 2x^3 + 3x^2 <u>- 18x -27</u>
p(x) = x^2(2x+3) <u>-9(2x+3)</u>
Now notice how x^2 and -9 have the same factor (2x+3). That means x^2 and -9 can go together:
p(x) = (x^2 - 9)(2x+3)
Factor it once more because there's a difference of squares:
p(x) = (x+3)(x-3)(2x+3)
Now just plug in whatever makes the each bracket equal 0:
x = -3, x = 3, and x = -3/2
Those are your zeros.
Answer:
a=6
b=10.39
Step-by-step explanation:
a=sin 30x12 or a=cos60x12
a=6
b=cos 30x12 or b=sin60x12
b=10.39
Answer:
b
Step-by-step explanation:
Answer:
k = - 2
Step-by-step explanation:
Given α and β are the zeros of x² - 6x + k = 0 , with
a = 1, b = - 6 and c = k , then
α + β = - 
= - 
= 6
αβ = 
= 
= k
Then solving
(α + β)² - 2αβ = 40
6² - 2k = 40
36 - 2k = 40 ( subtract 36 from both sides )
- 2k = 4 ( divide both sides by - 2 )
k = - 2
