X² + 1 = 0
=> (x+1)² - 2x = 0
=> x+1 = √(2x)
or x - √(2x) + 1 = 0
Now take y=√x
So, the equation changes to
y² - y√2 + 1 = 0
By quadratic formula, we get:-
y = [√2 ± √(2–4)]/2
or √x = (√2 ± i√2)/2 or (1 ± i)/√2 [by cancelling the √2 in numerator and denominator and ‘i' is a imaginary number with value √(-1)]
or x = [(1 ± i)²]/2
So roots are [(1+i)²]/2 and [(1 - i)²]/2
Thus we got two roots but in complex plane. If you put this values in the formula for formation of quadratic equation, that is x²+(a+b)x - ab where a and b are roots of the equation, you will get the equation
x² + 1 = 0 back again
So it’s x=1 or x=-1
Answer:
The volume is 1436.8
.
Step-by-step explanation:
-To find the volume of a sphere, you need the formula:

-Use the radius for the formula:

-Then, you solve:

×
× 
× 

-Round the answer to the nearest tenth:

So, therefore the volume is 1436.8
.
Answer:
2. x = -16 y = -10.5
3. x = 4
4. x = 3 y = 2/9 or 0.2222222222222...
Step-by-step explanation:
2.
in my stategy, you plus -5x + 8y = -4 with 6x - 8y = -12
+8y and -8y could delete each other, then y will be gone.
-5x + 6y = 1x = x because -5 + 6 = 1
so then you could got x = (-4) + (-12) which means x = -16
if x = -16 that will then means
(-5) x (-16) + 8y = -4
80 + 8y = -4
8y = -4 - 80
8y = -84
y = -10.5
3.
This question has already given you that y = -5
that means, 3x + 6 × (-5) = -18
3x + -30 = -18
3x = -18 - (-30)
3x = 12
x = 4
4.
Like the 2. qestion, you first plus the 2 equation together,
+9y + -9y = 0
-7x + 4x = -3x
-19 + 10 = -9
than means
-3x = -9
x = 3
then put the x = 3 in one of the equation.
4 x 3 - 9y = 10
12 - 9y = 10
-9y = 10 - 12
-9y = -2
-7 x 3 + 9y = -19
-21 + 9y = -19
9y = -19 + 21
9y = 2
y = 2/9 or 0.2222222222...
Wish this could help you!
Answer:
b. 4x^2 + 3x - 6
Step-by-step explanation:
The values of f(x) for the extremes of x are more positive than the value of f(x) for the middle x, so we know the parabola opens upward. That eliminates choice D.
It is probably easiest to evaluate the other expressions to see which one matches the given f(x) values. For the purpose, it is usually easier to use the Horner form of the equation.
a. f(-2) = (3(-2) +4)(-2) -6 = -2(-2) -6 = -2 ≠ 4
b. f(-2) = (4(-2) +3)(-2) -6 = -5(-2) -6 = 4 . . . . matches the given data point
c. Because (b) matches, we know this one will not.
The appropriate choice is B.
Answer:
4
Step-by-step explanation:
(9 x 2/3) x 2/3
9x 2 = 18
18/3 = 6
6 x 2 = 12
12/3 = 4
(9 x 2/3) x 2/3 = 4