Answer:
Solutions are 2, -1 + 0.5 sqrt10 i and -1 - 0.5 sqrt10 i
or 2, -1 + 1.58 i and -1 - 1.58i
(where the last 2 are equal to nearest hundredth).
Step-by-step explanation:
The real solution is x = 2:-
x^3 - 8 = 0
x^3 = 8
x = cube root of 8 = 2
Note that a cubic equation must have a total of 3 roots ( real and complex in this case). We can find the 2 complex roots by using the following identity:-
a^3 - b^3 = (a - b)(a^2 + ab + b^2).
Here a = x and b = 2 so we have
(x - 2)(x^2 + 2x + 4) = 0
To find the complex roots we solve x^2 + 2x + 4 = 0:-
Using the quadratic formula x = [-2 +/- sqrt(2^2 - 4*1*4)] / 2
= -1 +/- (sqrt( -10)) / 2
= -1 + 0.5 sqrt10 i and -1 - 0.5 sqrt10 i
Answer:
8n/9 - 4/3
Step-by-step explanation:
Answer:
sdfsdfesdfsdfsd
Step-by-step explanation:
Let x represent the number originally signed up.
.. 360/x -6 = 360/(x +3)
.. 360*(x +3) -6x(x +3) = 360x . . . . . multiply by the product of denominators
.. 360x +1080 -6x^2 -18x = 360x
.. x^2 +3x -180 = 0
.. (x +15)(x -12) = 0
Solutions are x = {-15, 12}
12 members went on the trip.
_____
The problem wording does not make clear whether the original number (12) or the number suggested by the bus company (15) went on the trip. It would be most reasonable for 15 to go, if the troop had people who were willing.
