What are the solutions to the equation r^3-7r^2-7r-8=0 ?

The solutions to the equation r^3-7r^2-7r-8=0 are r=8,r=-1/2+i(sqrt(3))/2 ,r=-1/2-i(sqrt(3))/2

Find the zeros of r^3-7r^2-7r-8=0

The zeros of r^3-7r^2-7r-8=0 are r=8,r=-1/2+i(sqrt(3))/2 ,r=-1/2-i(sqrt(3))/2

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

Popular >

r^{3} - 7 r^{2} - 7 r - 8 = 0

r = 8, r = - \frac{1}{2} + i \frac{3}{2}, r = - \frac{1}{2} - i \frac{3}{2}

Solution steps

r^{3} - 7 r^{2} - 7 r - 8 = 0

Factor

r^{3} - 7 r^{2} - 7 r - 8 : (r - 8) (r^{2} + r + 1)

(r - 8) (r^{2} + r + 1) = 0

Using the Zero Factor Principle:

ab = 0

then

a = 0

b = 0

r - 8 = 0 or r^{2} + r + 1 = 0

Solve

r - 8 = 0 : r = 8

Solve

r^{2} + r + 1 = 0 : r = - \frac{1}{2} + i \frac{3}{2}, r = - \frac{1}{2} - i \frac{3}{2}

The solutions are

r = 8, r = - \frac{1}{2} + i \frac{3}{2}, r = - \frac{1}{2} - i \frac{3}{2}

- x^{3} + x^{2} + 21 x - 45 = 0

\frac{x ^{5}}{4 + 5} = 13

x^{4} - 8 x^{2} + 4 = 0

1 0^{3} + x^{3} = 1^{3} + 1 2^{3}

(x^{2} + 3 x + 4) (x^{2} + 6 x + 4) = 0

What are the solutions to the equation r^3-7r^2-7r-8=0 ?
The solutions to the equation r^3-7r^2-7r-8=0 are r=8,r=-1/2+i(sqrt(3))/2 ,r=-1/2-i(sqrt(3))/2
Find the zeros of r^3-7r^2-7r-8=0
The zeros of r^3-7r^2-7r-8=0 are r=8,r=-1/2+i(sqrt(3))/2 ,r=-1/2-i(sqrt(3))/2