# Pre Calculus

posted by .

find all solutions of the equation

1. x^3+27=0

2. x^3-8=0

• Pre Calculus -

27+0 i = 27 e^i(0) = 27 cos 0 + i sin 0

27^(1/3)=3e^0 or 3e^i(2pi/3) or 3e^(4 pi/3)

= 3
or
= 3 cos 120 + 2i sin 120
= -1.5 + i sqrt 3
or
= -1.5 - i sqrt 3

## Similar Questions

1. ### Pre Calculus

find all exact real solutions of the equation. x^4-2x^2-24=0
2. ### Pre-Calculus

cos^2(x) + sin(x) = 1 - Find all solutions in the interval [0, 2pi) I got pi/2 but the answer says {0, pi/2, pi} Where does 0 and pi come from for solutions?
3. ### Pre calculus

Find all solutions of the equation tan^5 x - 9tan x =0. The answer is Ak\pi where k is any integer, the constant A=?
5. ### Pre-Calculus

Find all solutions of the equation and express them in the form a+bi 2x^2+3=2x
6. ### Pre-Calculus

Find all solutions of the equation and express them in the form a + bi. 36x^2 − 12x + 2 = 0
7. ### pre calculus

Find all of the solutions of the equation x^4-625i=0 and represent the solutions graphically.
8. ### pre calculus

Find all of the solutions of the equation x4-625i=0 and represent the solutions graphically. what is the next step to answer the question?
9. ### Pre calc

Find all primary solutions (i.e. 0 ≤ θ < 2π ) of the equation cos(2θ ) = 4 − 3 cos(θ ). Find all primary solutions (i.e. 0 ≤ θ < 2π ) of the equation cos(2θ )cos(θ ) = sin(2θ )sin(θ ). Please can somone help and …
10. ### Pre calc

Find all primary solutions (i.e. 0 ≤ θ < 2π ) of the equation cos(2θ ) = 4 − 3 cos(θ ). Find all primary solutions (i.e. 0 ≤ θ < 2π ) of the equation cos(2θ )cos(θ ) = sin(2θ )sin(θ ). Please can somone help and …

More Similar Questions